The Chemical Analysis of 

Argonne Premium Coal Samples

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UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1997

The Chemical Analysis of 

Argonne Premium Coal Samples

Edited by Curtis A. Palmer

U.S. GEOLOGICAL SURVEY BULLETIN 2144

This manual presents analytical data from currently 

recommended procedures as well as procedures used 

in the 1980’s by the geochemical laboratories of the 

U.S. Geological Survey for the chemical characterization 

of coal and a comparison of the results of these procedures 

for the Argonne Premium Coal samples.
U.S. DEPARTMENT OF THE INTERIOR

BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY

GORDON P. EATON, Director

For sale by U.S. Geological Survey, Information Services

Box 25286, Federal Center, Denver, CO 80225

Any use of trade, product, or firm names in this publication is for descriptive purposes only and

does not imply endorsement by the U.S. Government.

Published in the Eastern Region, Reston, Va.

Manuscript approved for publication July 10, 1995.

Library of Congress Cataloging in Publication Data

The chemical analysis of Argonne Premium Coal samples / edited by Curtis A. Palmer.

p. cm. — (U.S. Geological Survey bulletin ; 2144)

Includes bibliographical references.

Supt. of Docs. No.: I 19.3:B2144

1. Coal—United States—Analysis. I. Palmer, Curtis A. II. Series.

QE75.B9 no. 2144

[TP326.U6]

662.6¢22973—dc20 96–36480

CIP
III

CONTENTS

The Chemical Analysis of Argonne Premium Coal Samples: An Introduction

By Curtis A. Palmer............................................................................................. 1

Rehydration of Desiccated Argonne Premium Coal Samples

By Marta R. Krasnow and Robert B. Finkelman ................................................ 5

Determination of 62 Elements in 8 Argonne Premium Coal Ash Samples by 

Automated Semiquantitative Direct-Current Arc Atomic Emission

Spectrography

By Carol J. Skeen, B.J. Libby, and W.B. Crandell .............................................. 7

Determination of 18 Elements in 5 Whole Argonne Premium Coal Samples by 

Quantitative Direct-Current Arc Atomic Emission Spectrography

By Janet D. Fletcher and Carol J. Skeen ............................................................. 13

Determination of Major and Trace Elements in Eight Argonne Premium Coal 

Samples (Ash and Whole Coal) by X-Ray Fluorescence Spectrometry

By John R. Evans, George A. Sellers, Robert G. Johnson, Davison V. Vivit, 

and Judy Kent ............................................................................................. 19

Determination of 29 Elements in 8 Argonne Premium Coal Samples by 

Instrumental Neutron Activation Analysis

By Curtis A. Palmer............................................................................................. 25

Determination of Selected Elements in Coal Ash from Eight Argonne Premium 

Coal Samples by Atomic Absorption Spectrometry and Atomic Emission 

Spectrometry

By Michael W. Doughten .................................................................................... 33

Determination of 25 Elements in Coal Ash from 8 Argonne Premium Coal 

Samples by Inductively Coupled Argon Plasma-Atomic Emission Spectrometry

By Paul H. Briggs................................................................................................ 39

Determination of 33 Elements in Coal Ash from 8 Argonne Premium Coal 

Samples by Inductively Coupled Argon Plasma-Mass Spectrometry

By Allen L. Meier................................................................................................ 45

Determination of Mercury and Selenium in Eight Argonne Premium Coal 

Samples by Cold-Vapor and Hydride-Generation Atomic Absorption

Spectrometry

By Richard M. O’Leary....................................................................................... 51

Determination of Carbon, Hydrogen, and Nitrogen in Eight Argonne Premium 

Coal Samples by Using a Gas Chromatographic Analyzer with a Thermal

Conductivity Detector

By Carol J. Skeen and Zoe A. Brown.................................................................. 57

Compilation of Multitechnique Determinations of 51 Elements in 8 Argonne 

Premium Coal Samples

By Curtis A. Palmer and Sarah A. Klizas............................................................ 61
IV CONTENTS

Appendix 1. Comparison of the Concentrations of 51 Elements Determined by 

Multiple Analytical Techniques in 8 Argonne Premium Coal Samples.............. 77

Appendix 2. Statistical Parameters for the Data in Appendix 1 ................................. 96

CONVERSION FACTORS

Both metric and inch-pound units are used by the different authors. Conversion factors are given below.

For temperature conversions from degrees Celsius (°C) to degrees Fahrenheit (°F),

use the following:

(1.8  ́ °C) + 32 = °F

Standard reference materials.—The National Bureau of Standards (NBS) was

renamed the National Institute of Standards and Technology (NIST) in 1988. In this

report, standard reference materials from this agency are called NIST 1632a and so on,

and the certificates of analysis of the reference materials are cited as National Bureau of

Standards publications.

Multiply By To obtain

Length

nanometer (nm) 0.03937  ́ 10-6 inch

micrometer (mm) 0.03937  ́ 10-3 inch

millimeter (mm) 0.03937 inch

meter (m) 3.281 foot

inch 25.4 millimeter

Mass

picogram (pg) 1.543  ́ 10-11 grain

nanogram (ng) 1.543  ́ 10-8 grain

microgram (mg) 1.543  ́ 10-5 grain

milligram (mg) 1.543  ́ 10-2 grain

gram (g) 0.03527 ounce avoirdupois

Volume

microliter (mL) 0.016 minims

milliliter (mL) 0.0338 fluid ounce

cubic centimeter (cm3) 0.06102 cubic inch

Flow

liter per minute (L/min) 0.2642 gallon/minute

Force per unit area

pound per square inch (lb/in2) 6,895 pascal
1

THE CHEMICAL ANALYSIS OF

ARGONNE PREMIUM COAL SAMPLES

Edited by Curtis A. Palmer

The Chemical Analysis of Argonne Premium Coal Samples:

An Introduction

By Curtis A. Palmer

ABSTRACT

Methods used to determine the concentrations of

67 elements in 8 Argonne Premium Coal samples are

summarized in this bulletin. Seventeen different pro-cedures

involving 11 different techniques were used. Sample identification, sample protocol, and sample descriptions are presented.

INTRODUCTION

 This bulletin contains papers discussing the U.S. Geological Survey’s chemical analyses of eight Argonne Premium Coal samples. The papers present analytical results

obtained from all the methods used in the analyses and give

a comparison of the results for elements where more than

one technique was used. This paper describes the samples,

explains the numbering protocol used throughout this bulletin, and lists the elements whose concentrations were determined by each technique used.

A detailed description of the samples, the reasons for

their collection, and other background information have

been reported by Vorres (1990, 1993). Table 1 contains the

sample identification for the eight Argonne Premium Coal

samples used in this study, with the seam, location, rank,

and ash yield for each. The samples come from seven different States and range in rank from lignite to low volatile bituminous. The sample identification protocol is similar to that

used by Vorres (1990). It consists of a two- to four-letter

identifier that represents either the State or the seam from

which the sample was obtained, followed by one or more

spaces, the letters “PC” for Premium Coal, and a dash followed by sample numbers 1 through 8. In the papers that

follow, splits are identified by the addition of a dash and

another number after the sample number. For example, split

2 of Premium Coal sample 1 is identified as UF PC-1-2,

with UF designating the Upper Freeport coal seam from

which Premium Coal sample 1 was obtained.

Seventeen different procedures involving 11 different

techniques were used to determine concentrations of 67 different elements. Ten of these procedures required coal ash,

and the other seven used the whole coal. Table 2 shows the

Table 1. Sample identification, location, rank, and ash yield of

the eight Argonne Premium Coal samples analyzed in this work. 

[Ash yields are taken from table 1 of Doughten’s paper, this volume] 

Sample ID Seam State Rank

Ash

yield 

(%)

UF PC-1.............. Upper 

Freeport.

Pa. Medium 

volatile 

bituminous.

13.5

WY PC-2 ............ WyodakAnderson.Wyo. Subbituminous 8.5

IL PC-3 ............... Illinois No. 6 Ill. High volatile 

bituminous.

16.2

PITT PC-4........... Pittsburgh

(No. 8).

Pa. High volatile 

bituminous.

 9.2

POC PC-5 ........... Pocahontas 

No. 3.

Va. Low volatile 

bituminous.

5.3

UT PC-6.............. Blind 

Canyon.

Utah High volatile 

bituminous.

4.6

WV PC-7 ............ LewistonStockton.W. Va. High volatile 

bituminous.

19.4

ND PC-8 ............. Beulah-Zap N. Dak. Lignite 9.5
2 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 2. Tabulation of elements determined by different techniques.

[DCAES, direct-current arc atomic emission spectrography; XRF, X-ray fluorescence spectrometry; INAA, instrumental neutron activation analysis; ICAPAES, inductively coupled argon plasma-atomic emission spectrometry, (R), Reston, (D), Denver; ICAP-MS, inductively coupled argon plasma-mass spectrometry; AAS, atomic absorption spectrometry; CVAAS, cold-vapor AAS; HGAAS, hydride-generation AAS; CHN, carbon-hydrogen-nitrogen elemental

analysis; WC, whole coal] 

Element

Technique and material Total 

number

of 

procedures

 DCAES XRF INAA

WC

ICAPAES(R)

Ash

ICAPAES(D)

Ash

ICAP-MS

Ash

AAS

Ash

CVAAS

WC

HGAAS

WC

CHN

WC WC Ash WC Ash

H............ X 1 H

Li........... X X 2 Li

Be .......... X X X 3 Be

B............ X X2 2 B

C............ X 1 C

N............ X 1 N

Na.......... X X1 X X X 5 Na

Mg......... X X X1 X X2 5 Mg

Al........... X X X1 X X2 5 Al

Si ........... X X X1 X2 4 Si

P ............ X X1 X1 X X2 5 P

S ............ X1 1 S

Cl........... X1 1 Cl

K............ X X1 X XX2 5 K

Ca .......... X X X1 X X2 5 Ca

Sc........... X X X 3 Sc

Ti ........... X X X1 X X2 5 Ti

V............ X X X X 4 V

Cr........... X X X X X X X 7 Cr

Mn......... X X X1 X X 5 Mn

Fe........... X X X1 X XX2 6 Fe

Co.......... X X X X X 5 Co

Ni........... X X X X X X X 7 Ni

Cu.......... X X X X X X 6 Cu

Zn .......... X X X X X X 6 Zn

Ga.......... X X X 3 Ga

Ge.......... X X X 3 Ge

As .......... X X X 3 As

Se........... X X 2 Se

Br........... X 1 Br

Rb.......... X X X X 4 Rb

Sr........... X X X X X X 6 Sr

Y............ X X X X X 5 Y

Zr........... X X X X X2 5 Zr

Nb.......... X X X X 4 Nb

Mo......... X X 2 Mo

Ag.......... X X 2 Ag

Cd.......... X X4 2 Cd

Sn .......... X X 2 Sn

Sb .......... X X 2 Sb

Te........... X 1 Te

Cs .......... X X 2 Cs

Ba .......... X X X X X X X2 7 Ba

La .......... X X X X X3 5 La

Ce .......... X X X X X3 5 Ce

Pr........... X X3 2 Pr

Nd.......... X X X3 3 Nd

Sm ......... X X X3 3 Sm

Eu .......... X X X3 3 Eu

Gd.......... X3 1 Gd

Tb .......... X X3 2 Tb

Dy.......... X3 1 Dy

Ho.......... X3 1 Ho

Er........... X3 1 Er

Tm......... X3 1 Tm
INTRODUCTION 3

elements, listed by atomic number, whose concentrations

were determined by each procedure. Procedures include

two direct-current arc atomic emission spectrography

(DCAES) procedures, one on the ash and one on the whole

coal; four X-ray fluorescence spectrometry (XRF) procedures, including both wavelength- and energy-dispersive

procedures for the analysis of both the whole coal and the

ash; and four atomic absorption spectrometry (AAS) procedures, including flame and graphite furnace AAS on the ash,

cold-vapor atomic absorption spectrometry (CVAAS) procedures for mercury on the whole coal, and a hydride-generation AAS (HGAAS) procedure for selenium. Other

techniques include instrumental neutron activation analysis

(INAA) and combustion/gas chromatographic analyses for

carbon, hydrogen, and nitrogen (CHN), which were determined on the whole coal only. Five inductively coupled

argon plasma procedures were made on the ash only. Three

of these procedures used an acid digest: the two inductively

coupled argon plasma-atomic emission spectrometry

(ICAP-AES) procedures (one in Reston and one in Denver)

and the inductively coupled argon plasma-mass spectrometry (ICAP-MS) on the acid digest prepared in Denver. Two

additional procedures used a sinter digest: the ICAP-AES

and the ICAP-MS procedures in Denver. Ash yield (see

paper by Doughten, this volume) and moisture content (see

paper by Krasnow and Finkelman, this volume) are also

reported. A detailed description of each of these procedures

is given in the following papers.

In addition to the concentrations of 38 elements determined by DCAES on the ash, lower limits of detection were

reported for another 24 elements, making a total of 62 elements reported by DCAES in the paper by Skeen, Libby,

and Crandell. Of the 67 different elements with reported

concentrations, 51 were determined by more than one technique. Results obtained by different techniques are compared by Palmer and Klizas in this volume.

This bulletin is a greatly expanded version of a preliminary report edited by Palmer and Walthall (1991) that contained information on 58 elements, 33 of which had been

determined by more than one technique. All of the preliminary data were collected at the analytical facilities of the

U.S. Geological Survey (USGS) in Reston, Va., and represented the procedures used to analyze coal through 1990. In

1990, work was begun to develop a procedure to determine

trace-element concentrations by only high-precision techniques. The determination of several of the elements by

DCAES was replaced by ICAP-MS, a technique available

within the USGS only in laboratories in Denver, Colo.

Because the dissolution procedures for ICAP-MS and

ICAP-AES are the same, all routine ICAP-AES determinations on coal were moved to the Denver facilities. These two

techniques were appropriate for most of the elements previously determined by the Reston high-precision techniques:

INAA, XRF, and AAS. Those techniques, therefore, have

been dropped for routine analysis, although INAA is still

used for many samples when determinations on the whole

coal are necessary or when sample size is critical. One element determined by INAA and not determined with the new

procedures was selenium. A hydride-generation AAS

method was developed in Denver to determine selenium. A

Table 2. Tabulation of elements determined by different techniques—Continued. 

1Wavelength-dispersive procedure; all other XRF procedures are energy-dispersive XRF.

2Sinter digestion procedure; all other ICAP-AES procedures are acid digestion procedures.

3

Sinter digestion procedure; all other ICAP-MS procedures are acid digestion procedures.

4Graphite furnace AAS; all other AAS procedures are flame AAS.

Element

Technique and material Total 

number

of 

procedures

 DCAES XRF INAA

WC

ICAPAES(R)

Ash

ICAPAES(D)

Ash

ICAP-MS

Ash

AAS

Ash

CVAAS

WC

HGAAS

WC

CHN

WC WC Ash WC Ash

Yb .......... X X X3 3 Yb

Lu........... X 1 Lu

Hf........... X X3 2 Hf

Ta ........... X X3 2 Ta

W ........... X X3 2 W

Au .......... X 1 Au

Hg .......... X 1 Hg

Tl............ X 1 Tl

Pb........... X X X X4 4 Pb

Bi ........... X X 2 Bi

Th........... X X 2 Th

U ............ X X 2 U

TOTALS 18 38 14 23 29 18 25 33 4 1 1 3 207
4 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

new procedure to determine mercury by CVAAS was also

added. CHN information is routinely obtained by ultimate

and proximate analysis of coal by an outside laboratory,

although CHN is still determined in USGS laboratories on

some research samples.

The following chapters include papers modified from

the open-file report by Palmer and Walthall (1991), as well

as new papers describing the new Denver techniques. Results in each paper are reported in the manner in which

results are normally reported by the laboratory performing

the analysis. In all the papers except the last, results from

methods used to analyze ash are reported on an ash basis,

whereas results from methods used to analyze whole coal

are reported on a whole-coal basis. Similarly, concentrations of major rock-forming elements are reported on an

oxide basis or an element basis depending on the standard

practice of the laboratory performing the analysis. The units

parts per million (ppm) and micrograms per gram (mg/g) are

equivalent as are weight percent and percent (%); all results

in this report are on a weight basis.

The comparison chapter by Palmer (1991) in the openfile report has been completely rewritten by Palmer and Klizas as the last paper in this report to include all the new

techniques and a statistical analysis of results for all 51 elements that were determined by more than one procedure.

All results in the last paper are converted to an element

basis and a whole-coal basis and are expressed in weight

percent and parts per million. Although only eight samples

are included in this bulletin, comparison of the data for old

and new techniques is useful in determining the accuracy of

the data in the National Coal Resource Data System

(NCRDS), which contains data for over 13,000 coal and

rock samples, 7,400 of which are available on CD-ROM

(Bragg and others, 1994).

REFERENCES

Bragg, L.J., Oman, J.K., Tewalt, S.J., Oman, C.L., Rega,

N.H., Washington, P.M., and Finkelman, R.B., 1994, U.S.

Geological Survey coal quality (COALQUAL) data base—

Version 1.3: U.S. Geological Survey Open-File Report 94–

205 (CD-ROM). 

Palmer, C.A., 1991, Compilation of multi-element analysis of

eight Argonne Premium Coal samples for 33 elements, in

Palmer, C.A., and Walthall, F.G., eds., The chemical analysis

of Argonne Premium Coal samples: U.S. Geological Survey

Open-File Report 91–638, chap. I, p. 84–112.

Palmer, C.A., and Walthall, F.G., eds., 1991, The chemical analysis of Argonne Premium Coal samples. U.S. Geological Survey Open-File Report 91–638, 112 p.

Vorres, K.S., 1990, The Argonne Premium Coal Sample Program:

Energy and Fuels, v. 4, no. 5, p. 420–426.

———1993, Users handbook for the Argonne Premium Coal

Sample Program: Argonne National Laboratories Report

ANL/PCSP–93/1, 200 p.
5

Rehydration of Desiccated Argonne Premium Coal Samples

By Marta R. Krasnow and Robert B. Finkelman

ABSTRACT

Eight Argonne Premium Coal samples stored in polyethylene bottles for several years exhibited substantial moisture losses. The samples retained an average of 23 percent

of their original moisture content, with a range of 5 to 59

percent retention. Resaturated samples averaged 53 percent

of the original moisture, with a range of 14 to 95 percent. If

desiccated coal samples are to be analyzed, we recommend

that moisture contents be determined prior to analysis. Drying coal samples prior to analysis would be an acceptable

alternative if the original moisture content is known and the

sample does not pick up moisture between drying and

weighing for analysis.

INTRODUCTION

The Argonne National Laboratory has sealed its eight

Premium Coal samples in glass ampoules filled with an

inert gas (argon) to ensure that they retain their original

properties during storage (Vorres, 1990). Once the ampoules

are opened in a laboratory, however, sample alteration, such

as dehydration and oxidation, can occur.

EXPERIMENTAL

We experienced a situation in which Argonne Premium

Coal samples were stored in our laboratory for 2 to 4 years

in polyethylene bottles, which allowed the samples to dehydrate (see columns 1 and 2 of table 1). A substantial amount

of moisture had been lost from each sample during storage.

This paper is intended to illustrate the degree of dehydration

and to discuss the possibility of rehydrating the samples.

From 41 to 95 percent of the original moisture was lost

during the unregulated storage of the “aged” samples. Sample WY PC-2 lost almost 20 weight percent moisture, and

ND PC-8 lost more than 30 weight percent. Sample POC

PC-5 lost the least absolute amount of moisture, slightly

more than 0.5 weight percent.

To resaturate the samples, weighed splits of -100 mesh

coal were placed in uncovered petri dishes in a vacuum desiccator containing a barometer and a thermometer. Approximately 800 mL of deionized water was added to the base of

the desiccator. The samples were kept under atmospheric

pressure in the desiccator at 90 percent relative humidity

and 22 ̊C for 24 hours, after which they were removed from

the desiccator and weighed. Several samples had increases

far in excess of the original moisture loss. For example,

sample UF PC-1, which had lost about 1 weight percent

moisture, increased over 5 weight percent. This “excess”

moisture may be due to condensation on the coal particles.

We therefore allowed the resaturated samples to equilibrate

with the ambient atmosphere for 24 hours (22 ̊C–23 ̊C, 60–

64 percent relative humidity) prior to determining the moisture (referred to as resaturated moisture) by the American

Society for Testing and Materials (ASTM) (1996a) procedure (table 1, column 3).

After the 24-hour residency in the desiccator at the 90

percent relative humidity and subsequent equilibration,

moisture increased substantially in most samples. Sample

IL PC-3 regained 67 percent of the original moisture (table

1, column 1), and UT PC-6 regained 66 percent. Sample IL

PC-3 regained 5.36 weight percent moisture, and ND PC-8

gained almost 10 weight percent. Only sample UF PC-1

Table 1. Moisture of Argonne Premium Coal samples under

different conditions.

[Values are in weight percent; all moisture values were determined by

using the ASTM recommended procedure (ASTM, 1996a); Bit., bituminous; Sub., subbituminous; Lig., lignite] 

1Samples in ampoules; data from Vorres (1993).

2 Number in parentheses is the percentage of original moisture

content. 

Sample identification (1) (2) (3)

“Fresh”

samples1

“Aged”

samples2

After

resaturation Sample 2 Rank

UF PC-1 ................ Bit. 1.13 0.17 (15) 0.16 (14)

WY PC-2............... Sub. 28.09 8.79 (31) 9.76 (35)

IL PC-3.................. Bit. 7.97 1.41 (18) 6.77 (85)

PITT PC-4............. Bit. 1.65 .97 (59) 1.57 (95)

POC PC-5 ............. Bit. .65 .10 (15) .23 (35)

UT PC-6................ Bit. 4.63 .21 (05) 3.29 (71)

WV PC-7............... Bit. 2.42 .85 (35) 1.29 (53)

ND PC-8................ Lig. 32.24 1.94 (06) 11.90 (37)
6 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

showed no gain in moisture. Despite the substantial

increases in moisture for most samples, none of the samples, with the possible exception of PITT PC-4, recovered

all the moisture lost on drying.

Experiments on water desorption and adsorption have

been conducted by varying vapor pressure and holding the

temperature constant, usually less than 40 ̊C (Gauger, 1945;

Allardice and Evans, 1978). Results of the experiments indicate that, once dry, a coal sample will not adsorb enough

water to regain its original moisture content. There is no

generally accepted mechanism to explain this phenomenon

(Allardice and Evans, 1978); however, several theories have

been offered. These include (1) the shrinking of coal on drying, which causes a collapse of some capillaries, so that the

dried material can no longer hold or take up as much water

as it held originally, and (2) the replacement of moisture on

the walls of some capillaries by adsorbed gases, making it

difficult to re-wet the capillaries (Gauger, 1945).

Vorres and Kolman (1988) and Vorres and others

(1988) conducted drying and rehydration studies of

Argonne Premium Coal samples. They concluded that coal

rank, particle size, and degree of oxidation affected moisture removal and replacement.

The Argonne Premium Coal samples behave in a typical fashion with respect to rehydration. Improper storage

can lead to substantial moisture loss. Resaturation generally

will restore some of the lost moisture. These observations

on moisture loss are important if measurements of physical

properties are to be made on samples that have been stored

under noncontrolled conditions for any length of time.

These observations are also important for calculations

involving chemical analysis of the raw coal (for example,

instrumental neutron activation analysis or X-ray fluorescence analysis). Assuming that the coal samples have

retained their original moisture contents can lead to errors

of as much as 30 percent for low-rank coals (lignites and

subbituminous: ND PC-8 and WY PC-2, respectively).

Even for higher rank coal (for example, IL PC-3), the errors

can be as high as 6.5 percent.

DISCUSSION

We recommend the following procedures to minimize

errors caused by desiccation (especially for low-rank coal):

1. After the ampoules are opened, samples should be stored

in a way to minimize dehydration.

2. Moisture content of each coal sample should be determined just prior to chemical analysis of whole coal.

3. If there is insufficient sample for moisture determination,

rehydrate the sample to reduce the error. 

The ASTM method for determining equilibrium moisture (ASTM, 1996b, D 1412–93) could be used to rehydrate

the sample, but the method requires at least a 20-g sample,

more time, and more equipment than the procedure

described in this paper.

An alternative method would be to analyze a moisturefree sample by drying it (105 ̊C for 24 hours) prior to analysis. Two assumptions are necessary: (1) that the published

moisture value is applicable so that the chemical analysis

can be recalculated to an as-received basis, and (2) that the

sample does not pick up moisture between drying and

weighing for analysis.

REFERENCES

Allardice, D.J., and Evans, D.G., 1978, Moisture in coal, in Karr,

C.C., Jr., ed., Analytical methods for coal and coal products

(v. 1): New York, Academic Press, chap. 7, p. 247–262.

American Society for Testing and Materials (ASTM), 1996a,

ASTM Designation D 3173–87, Standard test method for

moisture in the analysis sample of coal and coke; 1996

Annual Book of ASTM Standards, v. 05.05, Gaseous fuels;

Coal and coke, p. 289–290.

———1996b, ASTM Designation D 1412–93, Standard test

method for equilibrium moisture of coal at 96 to 97 percent

relative humidity and 30°C; 1996 Annual Book of ASTM

Standards, v. 05.05, Gaseous fuels; Coal and coke, p. 188–

191.

Gauger, A.W., 1945, Condition of water in coal, in Lowery, H.H.,

ed., Chemistry of coal utilization (v. 1): New York, J. Wiley &

Sons, p. 600–626.

Vorres, K.S., 1990, The Argonne Premium Coal Sample Program:

Energy and Fuels, v. 4, no. 5, p. 420–426. 

———1993, Users handbook for the Argonne Premium Coal samples: Argonne National Laboratory [Report] ANL/PCSP–

93/1, 200 p.

Vorres, K.S., Kolman, R., and Griswold, T., 1988, Kinetics of vacuum drying and rehydration of Illinois #6 coal samples.

Implications for pore structure: Preprints, Fuel Chemistry

Division, American Chemical Society, v. 33, no. 2, p. 333–

342.

Vorres, K.S., and Kolman, R., 1988, Kinetics of the vacuum drying

and rehydration in nitrogen of coals from the Argonne Premium Coal Sample Program: Preprints, Fuel Chemistry Division, American Chemical Society, v. 33, no. 3, p. 7–16.
7

Determination of 62 Elements in 8 Argonne Premium Coal Ash Samples 

by Automated Semiquantitative Direct-Current Arc 

Atomic Emission Spectrography

By Carol J. Skeen, B.J. Libby, and W.B. Crandell

ABSTRACT

The automated semiquantitative direct-current arc

atomic emission spectrographic method was used to determine concentrations of 62 elements in 8 Argonne Premium

Coal ash samples. Ashed samples of all eight coals were

analyzed in triplicate to verify precision of the method. The

precision for most elements was within ±10 percent. The

accuracy of this method is assumed to be limited to +50 percent or -33 percent because of the nature of the standard

curves for each of the elements. Adjustments to the computer program were implemented to account for unique

matrix interferences in these particular coal ash samples.

INTRODUCTION

Emission spectrographic analysis is based on the emission of light by atoms and ions returning to ground state

after excitation in a direct-current (dc) arc. The light is

passed through the slit of a spectrograph and diffracted by a

grating. The slit image is focused on a photographic plate.

Distinct wavelength positions for each element indicate the

presence of that element, and the darkness of the resulting

specific slit image is proportional to the concentration of the

specific element present.

The automated dc atomic emission spectrographic

analysis of a wide variety of geologic materials is a rapid,

economical method for evaluating both the major- and

trace-element composition. A total of 62 elements can be

determined (Dorrzapf, 1973). This computerized procedure

is semiquantitative, because it calculates concentrations by

using prestored coefficients calculated from previously

arced standards. 

EXPERIMENTAL

In preparation of the samples for arcing, 15 mg of the

ashed sample (-100 mesh) was mixed with 30 mg of graphite and transferred to a graphite crater electrode. The standard operating procedures for the spectrographic analysis

are listed in table 1 (Dorrzapf and others, 1989). The Helz

jet was used in preference to a Stallwood jet, because it simplifies the procedure for changing samples (Stallwood,

1954; Shaw and others, 1958; Helz, 1964). An iron bead

Table 1. Photoplate preparation conditions.

[Table modified from Dorrzapf and others (1989, table 4). A, ampere;

ASTM, American Society for Testing and Materials; dc, direct current; L,

liter; min, minute; s, second; V, volt] 

Electrodes ........................ Cathode: ASTM type C–6, 50 mm 

long. Anode: 6.3-mm diameter, thinwalled graphite (Ultra Carbon no. 

3170).

Electrode charge .............. 15 mg sample + 30 mg graphite (type 

UCP–2, 200 mesh).

Spectrograph.................... 3.4-m Ebert (Jarrell-Ash Mark III).

Power source.................... 325 V, open circuit.

Excitation......................... 15-A dc arc, set with empty graphite 

electrodes.

Arc gap ............................ 4 mm, maintained throughout arcing.

Exposure .......................... 20 s at 5 A followed by 130 s at 15 A, 

continuous arcing.

Atmosphere...................... 70% Ar + 30% O2; 6.6 L/min flow rate, 

with top of Helz jet nozzle 2 mm 

below top of electrode.

Wavelength range ............ 230.0–470.0 nm; first order.

Grating............................. 600 grooves/mm; 0.5 nm/mm reciprocal linear dispersion.

Slit.................................... 25 μm wide and 2 mm high.

Filter................................. 14% transmission neutral-density filter 

at slit.

Illumination ..................... Arc image focused on collimator by 

450-mm focal-length cylindrical 

quartz lens at slit.

Mask at collimator........... 18 mm.

Emulsion.......................... Eastman-Kodak III-0 (102 ¥ 508 mm 

plates).

Processing........................ Eastman-Kodak D-19 developer, 

3.25 min at 20°C stirred by nitrogen 

bursts; Eastman-Kodak indicator stop 

bath, 30 s; Eastman-Kodak fixer, 

10 min; wash, 20–30 min at 20°C; 

Eastman-Kodak photo-flow, 1 min; 

and dry with warm air for 30 min.
8 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

was arced first and exposed on the plate for the iron calibration reference spectrum. Then each sample was arced at 5

amperes (A) for 20 seconds and then at 15 A for 130 seconds. For the iron and for each sample and standard, a cadmium lamp was exposed in two windows as a reference to

be used on the scanning microphotometer.

The photoplate was developed and processed according to standard U.S. Geological Survey (USGS) procedures

(Helz and others, 1969). The intensities of the spectra on the

plate were recorded by a scanning microphotometer (Helz,

1965, 1973). The data were processed by a Hewlett-Packard

2100 computer, and a report was generated with the 62-element concentration information. This report was evaluated

by the analyst, who verified the values reported (Golightly

and others, 1977; Dorrzapf and others, 1989).

Programs for data collection and interpretation that

were written (Walthall, 1974) for use on a mainframe computer were adapted for use on a minicomputer system (Thomas, 1979). The specific details about the procedure for

calibration and the algorithm used for calculations were

summarized by Dorrzapf and others (1989). 

RESULTS AND DISCUSSION

For eight Argonne Premium Coal samples, an in-depth

study was made for specific interference corrections in addiTable 2. Element concentrations determined by direct-current arc spectrographic analyses of NIST standard reference

material coal fly ash.

[Concentrations are in percentages (%) for the first nine elements (Si through Mn) and in micrograms per gram (μg/g) for the remaining

elements (As through Zr). NIST, National Institute of Standards and Technology, formerly the National Bureau of Standards; SD, standard deviation; USGS, U.S. Geological Survey] 

1Values taken from NIST Certificates 1633 (National Bureau of Standards, 1975) and 1633a (National Bureau of Standards, 1979).

Values with no error listed are NIST information values; all others are NIST certified values.

2Average of 35 determinations Feb. to July 1983.

3Average of 31 determinations June 1983 to Mar. 1984.

4Lower limit of determination.

Element

NIST 1633 NIST 1633a

NIST value1

 (mean ± SD)

 USGS

 average2

 NIST value1

(mean ± SD)

 USGS

 average3

Si (%)................ 27±3.3 22.8±0.8 26±2.6

Al...................... 17±2.8 14 18±3.1

Fe...................... 8.0±0.93 9.40±0.10 11±1.7

Mg .................... 2.2±0.32 .455±0.010 .71±0.14

Ca ..................... 5.4±1.2 1.11±0.01 1.3±0.31

Na ..................... .25±0.03 .17±0.01 .16±0.03

K....................... 1.72 1.3±0.15 1.88±0.06 1.5±0.19

Ti ...................... .80±0.15 .8 .85±0.18

Mn .................... .0493±0.0007 .076±0.11 .0190 .026±0.08

As (μg/g) .......... 61±6 4<100 145±15 190±49

B ....................... 430 440±46 32±4.0

Ba ..................... 1,600± 490 1,500 910±160

Be ..................... 12 15±1.5 12 14±1.9

Ce ..................... 170±29 180 160±53

Co ..................... 38 38±4.9 46 38±6.2

Cr...................... 131±2 120±23 196±6 180±33

Cu ..................... 128±5 100±25 118±3 93±21

Eu ..................... 3.1±0.5 4 3.4±0.6

Ga ..................... 49 39±5.8 58 54±11

La...................... 96±13

Mo .................... 29 28±6.2

Nd..................... 60 ±15 100±29

Ni...................... 98±3 110 ±15 127±4 140±19

Pb...................... 70±4 74 ±9.0 72.4±0.4 76±12

Sc...................... 25 ±4.0 40 29±5.7

Sr ...................... 1,380 1,700 ±30 830±30 900±140

V....................... 214±8 200 ±24 300 240±36

Y....................... 53 ±7.8

Yb..................... 6.6 ±0.9

Zr ...................... 180 ±29
AUTOMATED SEMIQUANTITATIVE DIRECT-CURRENT ARC ATOMIC EMISSION SPECTROGRAPHY 9

Table 3. Element concentrations determined by direct-current arc spectrographic analyses of the Argonne Premium Coal samples.

[Concentrations are in percentages (%) for the first 10 elements and in micrograms per gram (μg/g) for the other 52 elements. H, interference] 

Element UF PC-1-1 UF PC-1-2 UF PC-1-3 WY PC-2-1 WY PC-2-2 WY PC-2-3 IL PC-3-1 IL PC-3-2 IL PC-3-3

Si (%)............ 22 22 25 15 15 17 22 20 25

Al.................. 15 19 19 5.0 6.4 7.2 12 12 13 

Fe ................. 12 9.9 13 3.0 3.0 3.6 14 14 16 

Mg ............... .98 1.1 1.2 3.9 4.6 4.4 .69 .68 .77

Ca ................ 5.1 4.4 4.7 12 15 17 9.6 9.4 11

Na ................. .31 .35 .34 1.4 1.9 1.4 .99 .89 .91

K................... 2.3 2.1 2.2 .36 .44 .36 1.5 1.6 1.7

Ti .................. .45 .29 .44 .35 .43 .48 .38 .40 .45

P.................... <.068 <.068 <.068 .24 .31 .39 <.068 <.068 <.068

Mn ................ .041 .038 .043 .049 .032 .036 .066 .064 .070

Ag (μg/g)...... 1.4 1.5 1.6 .65 .85 .88 2.2 2.6 2.4

As ................. 230 280 160 <100 <100 <100 <100 <100 100

Au................. <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8

B ................... 140 350 180 870 740 860 730 680 780

Ba ................. 300 320 290 3,400 3,700 4,200 320 330 470

Be ................. 11 8.9 11 1.6 1.6 1.8 5.5 5.9 6.6

Bi .................. <10 <10 <10 <10 <10 <10 <10 <10 <10

Cd ................. <32 <32 <32 <32 <32 <32 <32 <32 <32

Ce ................. <63 74 <63 74 120 110 <200 <200 170

Co ................. 28 22 29 12 17 16 22 21 26

Cr.................. 160 130 140 56 74 70 220 220 260

Cu ................. 130 120 140 130 160 160 82 69 58

Dy................. <22 <22 <22 <22 <22 <22 <22 <22 <22

Er .................. <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6

Eu ................. <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2

Ga ................. 45 47 47 26 31 29 29 27 31

Gd................. <32 <32 <32 <32 <32 <32 <32 <32 <32

Ge ................. 26 25 29 <4.6 <4.6 <4.6 52 52 60

Hf.................. <15 <15 <15 <15 <15 <15 <15 <15 <15

Ho................. <68 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8

In................... <10 <10 <10 <10 <10 <10 <10 <10 <10

Ir ................... <15 <15 <15 <15 <15 <15 <15 <15 <15

La.................. 64 39 50 56 77 84 54 55 63

Lu ................. <15 <15 <15 <15 <15 <15 <15 <15 <15

Mo ................ 12 9.3 12 7.6 7.8 8.2 34 30 32

Nb................. 12 10 15 14 15 21 12 14 20

Nd................. 75 <32 37 <68 <68 <68 <68 <68 40

Ni.................. 100 95 110 57 64 64 130 120 150

Os ................. <15 <15 <15 <15 <15 <15 <15 <15 <15

Pb.................. 77 74 82 31 48 41 87 78 88

Pd.................. <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0

Pr .................. <100 <100 <100 <100 <100 <100 <100 <100 <100

Pt .................. <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2

Re ................. <10 <10 <10 <10 <10 <10 <10 <10 <10

Rh ................. <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2

Ru ................. <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2 <2.2

Sb.................. <68 <68 <68 <68 <68 <68 <68 <68 <68

Sc.................. 19 11 16 12 17 18 16 16 17

Sm ................ <10 <10 <10 <10 <10 <10 <10 <10 <10

Sn.................. 13 12 12 6.4 10 14 10 15 20

Sr .................. 490 420 490 2,000 2,800 3,100 250 230 270

Ta.................. <320 <320 <320 <320 <320 <320 <320 <320 <320

Tb ................. <32 <32 <32 <32 <32 <32 <32 <32 <32

Th ................. <46 <46 <46 <46 <46 <46 <46 <46 <46

Tl .................. <10 <10 <10 <10 <10 <10 <10 <10 <10

Tm ................ <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6

U................... <220 <220 <220 <220 <220 <220 <220 <200 <200

V................... 130 99 130 86 110 120 140 140 160

W .................. <15 <15 <15 <15 <15 <15 <15 <15 <15

Y................... 46 22 36 28 36 42 27 29 32

Yb................. 6.2 6.1 6.4 2.7 3.5 4.1 3.5 3.6 4.2

Zr .................. 96 55 90 140 200 250 86 96 140
10 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 3. Element concentrations determined by direct-current arc spectrographic analyses of the Argonne Premium Coal samples—

Continued. 

Element PITT PC-4-1 PITT PC-4-2 PITT PC-4-3 POC PC-5-1 POC PC-5-2 POC PC-5-3

Si (%) .............................. 26 29 32 18 17 19

Al..................................... 24 21 24 12 14 14

Fe..................................... 19 20 22 9.8 8.3 10

Mg................................... .71 .70 97 1.9 2.0 2.0

Ca .................................... 5.0 3.6 4.7 10 11 12

Na.................................... .42 .36 .40 2.4 2.4 2.5

K...................................... 1.4 1.3 1.5 .65 .63 .73

Ti ..................................... .64 .57 .64 .53 .47 .58

P ...................................... <.068 <.068 <.068 <.068 <.068 <.068

Mn................................... .033 .041 .042 .045 .043 .050

Ag (μg/g)......................... .95 .94 1.0 1.8 1.8 2.0

As .................................... 210 180 160 350 210 270

Au.................................... <6.8 <6.8 <6.8 <6.8 <6.8 <6.8

B...................................... 530 580 570 320 310 360

Ba .................................... 390 370 490 3,600 3,600 4,900

Be .................................... 12 13 13 14 11 13

Bi..................................... 22 17 <10 <10 <10 <10

Cd.................................... <32 <32 <32 <32 <32 <32

Ce .................................... <200 <200 <200 220 190 270

Co.................................... 31 25 30 45 44 56

Cr..................................... 220 190 220 170 150 180

Cu.................................... 58 89 66 420 290 380

Dy.................................... <22 <22 <22 <22 <22 <22

Er..................................... <4.6 <4.6 <4.6 <4.6 <4.6 <4.6

Eu .................................... <2.2 <2.2 <2.2 <2.2 <4.2 <2.2

Ga.................................... 57 43 54 42 40 47

Gd.................................... <32 <32 <32 <32 <32 <32

Ge.................................... 13 13 12 8.7 8.2 9.2

Hf .................................... <150 <150 <150 <15 <15 <15

Ho.................................... <6.8 <6.8 <6.8 <6.8 <6.8 <6.8

In ..................................... <10 <10 <10 <10 <10 <10

Ir...................................... <15 <15 <15 <15 <15 <15

La .................................... 60 66 62 130 130 150

Lu .................................... <15 <15 <15 <15 <15 <15

Mo................................... 9.4 7.4 9.0 37 41 46

Nb.................................... 18 22 18 24 14 22

Nd.................................... 47 46 35 100 130 110

Ni..................................... 150 130 150 120 110 140

Os .................................... <15 <15 <15 <15 <15 <15

Pb .................................... 79 75 84 220 160 220

Pd .................................... <1.0 <1.0 <1.0 <1.0 <1.0 <1.0

Pr..................................... <100 <100 <100 <100 <100 <100

Pt ..................................... <2.2 <2.2 <2.2 <2.2 <2.2 <2.2

Re .................................... <10 <10 <10 <10 <10 <10

Rh.................................... <2.2 <2.2 <2.2 <2.2 <2.2 <2.2

Ru.................................... <2.2 <2.2 <2.2 <2.2 <2.2 <2.2

Sb .................................... <68 <68 <68 <68 <68 <68

Sc..................................... 20 19 22 24 24 28

Sm ................................... <10 <10 <10 14 13 16

Sn .................................... 18 11 13 2,800 550 720

Sr..................................... 960 900 1,100 2,000 1,900 2,300

Ta..................................... <320 <320 <320 <320 <320 <320

Tb .................................... <32 <32 <32 <32 <32 <32

Th .................................... <46 <46 <46 <46 <46 <46

Tl..................................... <10 <10 <10 <10 <10 <10

Tm................................... <4.6 <4.6 <4.6 <4.6 <4.6 <4.6

U...................................... <220 <220 <220 <220 <220 <220

V...................................... 130 130 150 130 120 150

W..................................... <15 <15 <15 <15 <15 <15

Y...................................... 31 36 33 86 81 92

Yb.................................... 6.9 5.5 5.2 8.7 8.8 7.9

Zr..................................... 110 160 120 250 200 220
AUTOMATED SEMIQUANTITATIVE DIRECT-CURRENT ARC ATOMIC EMISSION SPECTROGRAPHY 11

Table 3. Element concentrations determined by direct-current arc spectrographic analyses of the Argonne Premium Coal samples—

Continued. 

Element UT PC-6-1 UT PC-6-2 UT PC-6-3 WV PC-7-1 WV PC-7-2 WV PC-7-3 ND PC-8-1 ND PC-8-2 ND PC-8-3

Si (%)............ 16 20 20 22 30 28 5.7 6.6 6.6

Al.................. 6.8 7.8 6.3 17 22 21 2.2 3.0 2.2

Fe.................. 4.6 5.9 5.1 1.8 2.3 2.1 3.7 4.5 3.5

Mg ................ .93 .82 .89 .66 .43 .40 5.5 5.4 5.3

Ca ................. 6.0 6.3 6.3 .40 .31 .49 13 14 15

Na ................. 1.9 1.4 1.4 .19 .18 .19 H 2.6 H

K................... .47 .31 .36 2.0 1.7 1.8 .40 .35 .41

Ti .................. .40 .43 .40 .95 .91 .90 .18 .18 .20

P.................... <.068 <.068 <.068 .086 <.068 <.068 <.13 .11 .098

Mn ................ .014 .010 .016 .0092 .012 .010 .11 .11 .11

Ag (μg/g)...... 12 8.9 9.6 2.6 2.2 2.2 <.10 <.10 <.10

As ................. <220 <220 <220 <220 <220 <220 <220 <220 <220

Au................. <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8

B ................... >1,000 >1,000 >1,000 150 480 250 500 800 810

Ba ................. 750 670 900 660 740 640 5,300 7,400 5,700

Be ................. 3.3 5.2 4.4 15 16 16 2.8 3.5 2.4

Bi .................. <22 <22 <22 <22 <22 <22 <22 <22 <22

Cd ................. <22 <22 <22 <22 <22 <22 <22 <22 <22

Ce ................. 160 160 130 130 140 130 <63 <63 <63

Co ................. 15 13 14 3630 31 5.7 6.0 5.7 5.7

Cr.................. 110 85 120 220 180 210 25 25 26

Cu ................. 69 52 66 90 85 68 41 40 75

Dy................. <10 <10 <10 <10 <10 <10 <10 <10 <10

Er .................. <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6 <4.6

Eu ................. <.68 <.68 2.5 2.4 2.5 4.6 <.68 <.68 <.68

Ga ................. 32 19 28 68 56 59 19 16 20

Gd................. <22 <22 <22 <22 <22 <22 <22 <22 <22

Ge ................. <4.6 <4.6 <4.6 5.5 <4.6 6.2 <4.6 <4.6 <4.6

Hf.................. <10 <10 <10 <10 <10 <10 <10 <10 <10

Ho................. <1.5 <1.5 <1.5 3.2 <1.5 1.7 <1.5 <1.5 <1.5

In................... <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8

Ir ................... <10 <10 <10 <10 <10 <10 <10 <10 <10

La.................. 66 64 62 72 74 64 37 40 39

Lu ................. <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8 <6.8

Mo ................ 12 8.4 11 7.0 8.4 6.3 8.6 8.2 8.7

Nb................. 10 11 12 13 19 23 6.6 5.3 6.4

Nd................. 64 <150 <150 97 100 90 <32 <32 <150

Ni.................. 84 89 87 120 100 110 17 17 22

Os ................. <10 <10 <10 <10 <10 <10 <10 <10 <10

Pb.................. 45 36 43 93 81 69 28 22 32

Pd.................. <.68 <.68 <.68 <.68 <.68 <.68 <.68 <.68 <.68

Pr .................. 9.5 9.3 8.4 10 9.3 <6.8 <6.8 <6.8 7.3

Pt .................. <1.5 <1.5 <1.5 <1.5 <1.5 <1.5 <1.5 <1.5 <1.5

Re ................. <10 <10 <10 <10 <10 <10 <10 <10 <10

Rh ................. <1.5 <1.5 <1.5 <1.5 <1.5 <1.5 <1.5 <1.5 <1.5

Ru ................. <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0

Sb.................. <32 <32 <32 <32 <32 <32 <32 <32 <32

Sc.................. 16 15 14 36 31 32 9.2 9.1 10

Sm ................ 8.0 8.2 7.8 8.9 8.7 <3.2 <3.2 <3.2 4.9

Sn.................. 8.8 5.9 9.4 11 8.4 10 <4.6 <4.6 13

Sr .................. 1,800 2,000 2,000 390 320 370 6,200 6300 7300

Ta.................. <320 <320 <320 <320 <320 <320 <320 <320 <320

Tb ................. <32 <32 <32 <32 <32 <32 <32 <32 <32

Th ................. <46 <46 <46 <46 <46 <46 <46 <46 <46

Tl .................. <10 <10 <10 <10 <10 <10 <1015 <10 <10

Tm ................ <3.2 <3.2 <3.2 <3.2 <3.2 <3.2 <3.2 <3.2 <3.2

U................... <150 <150 <150 <150 <150 <150 <150 <150 <150

V................... 82 78 79 160 180 150 38 38 37

W .................. <10 <10 <10 <10 <10 <10 <10 <10 <10

Y................... 41 42 34 50 52 39 24 27 25

Yb................. 4.9 4.4 4.6 9.2 7.3 7.1 2.3 2.0 2.1

Zr .................. 260 280 200 200 150 140 130 130 140
12 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

tion to those that were automatically performed. Because of

heterogeneity problems associated with barium, coupled

with the suppression of the most sensitive analytical lines

for barium due to the matrices of these coals, values from

less sensitive lines were used. The values for strontium were

improved after correcting for interferences from iron and

nickel.

This semiquantitative approach achieves ranges and

detectability comparable to those of the visual estimation

procedure (Myers and others, 1961). Because the standards

used do not closely match the approximate composition of

the ash samples to be analyzed, the expected accuracy is

limited to ±1 step, which corresponds to roughly +50 percent or -33 percent of the reported value.

In the analyses of these Premium Coals, the National

Institute of Standards and Technology (NIST) standard reference materials NIST 1633 and NIST 1633a (National

Bureau of Standards, 1975, 1979) were included as control

samples for evaluation of both precision and accuracy of

this method. Table 2 lists the concentrations provided by

NIST certificates, the mean concentrations determined over

a 5-month period, and the associated relative standard deviations. Compositions determined for coal ashes are within

the limits of precision and accuracy for which the method

was designed. The high relative standard deviations for barium and zirconium indicate the heterogeneity documented

for these reference materials (Filby and others, 1985). Heterogeneity possibly explains the large range of values for

barium and zirconium in the Premium Coals as well as the

interferences discussed above.

Table 3 lists data for all 62 elements in these eight

Argonne Premium Coals. The “less than” symbol indicates

that the concentration is less than the lower limit for a value

that can be determined for that element, and the “greater

than” symbol indicates that the concentration is greater than

the highest value that can be reliably determined for that

element. An “H” denotes the occurrence of an unresolved

interference. Major elements are reported in percentages,

and the trace elements in micrograms per gram.

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Dorrzapf, A.F., Jr., 1973, Spectrochemical computer analysis—

Argon-oxygen D-C arc method for silicate rocks: U.S. Geological Survey Journal of Research, v. 1, no. 5, p. 559–562.

Dorrzapf, A.F., Jr., Skeen, C.J., and Crandell, W.B., 1989, Automated semiquantitative direct-current arc spectrographic

determination of 64 elements in coal ash, in Golightly, D.W.,

and Simon, F.O., eds., Methods for sampling and inorganic

analysis of coal: U.S. Geological Survey Bulletin 1823, p.

21–26. 

Filby, R.H., and others, 1985, Evaluation of geochemical standard

reference materials for microanalysis: Analytical Chemistry,

v. 57, no. 2, p. 551–555.

Golightly, D.W., Dorrzapf, A.F., Jr., and Thomas, C.P., 1977, Sets

of spectral lines for spectrographic thermometry and monometry in d.c. arcs of geologic materials: Spectrochimica Acta, v.

32B, p. 313–323.

Helz, A.W., 1964, A gas jet for D-C arc spectroscopy: U.S. Geological Survey Professional Paper 475–D, p. D176–D178.

———1965, The problem of automatic plate reading and computer interpretation for spectrochemical analysis: U.S. Geological Survey Professional Paper 525–B, p. B160–B162.

———1973, Spectrochemical computer analysis—Instrumentation: U.S. Geological Survey Journal of Research, v. 1, no. 4,

p. 475–482.

Helz, A.W., Walthall, F.G., and Berman, S., 1969, Computer analysis of photographed optical emission spectra: Applied Spectroscopy, v. 23, p. 508–512.

Myers, A.T., Havens, R.G., and Dunton, P.J., 1961, A spectrochemical method for the semiquantitative analysis of rocks,

minerals, and ores: U.S. Geological Survey Bulletin 1084–I,

p. 207–215.

National Bureau of Standards, 1975, National Bureau of Standards

certificate of analysis, standard reference material 1633, trace

elements in coal fly ash: Washington, D.C., National Bureau

of Standards, 2 p.

———1979, National Bureau of Standards certificate of analysis,

standard reference material 1633a, trace elements in coal fly

ash: Washington, D.C., National Bureau of Standards, 2 p.

Shaw, D.M., Wickremasenghe, O., and Yip, C., 1958, A simple

device for the spectrochemical analysis of minerals in an inert

atmosphere using the Stallwood jet: Spectrochimica Acta, v.

13, p. 197–201.

Stallwood, B.J., 1954, Air-cooled electrodes for the spectrochemical analysis of powders: Journal of Optical Society of America, v. 44, p. 171–172.

Thomas, C.P., 1979, A minicomputer-based emission spectrographic analysis system dependent on scanning microphotometry: Applied Spectroscopy, v. 33, p. 604–619.

Walthall, F.G., 1974, Spectrochemical computer analysis—

Program description: U.S. Geological Survey Journal of

Research, v. 2, no. 1, p. 61–71.
13

Determination of 18 Elements in 5 Whole Argonne Premium Coal Samples by 

Quantitative Direct-Current Arc Atomic Emission Spectrography

By Janet D. Fletcher and Carol J. Skeen

ABSTRACT

Quantitative multiple-element analysis of whole

Argonne Premium Coal samples by direct-current arc

atomic emission spectrography is possible with the use of a

lithium carbonate buffer. Two spectrographic methods are

described for the determination of 18 trace elements in 100-

mg samples of coal. Overall concentrations for calibration

standards range from a low of 2 μg/g to a high of 3 weight

percent. For concentrations well above the lower determination limit, the typical accuracy is within ±20 percent, and

the general precision of the method is ±10 percent.

INTRODUCTION

Most atomic-spectroscopic methods are designed for

the analysis of ash from pulverized coals that have been oxidized at 500 ̊C or 750 ̊C (ASTM, 1984). The direct-current

(dc) arc functions well for ash that is mixed with graphite

powder, and many elements are effectively preconcentrated

by the ashing process, thus providing improved detectability

(Dorrzapf, 1973), but certain elements associated with

organic phases, such as porphyrins, organometallics, or acid

salts, may be volatilized and lost during the ashing process.

The elements Ag, B, Ga, Ge, Mo, Ni, and Ti, which potentially can be determined by dc arc spectroscopy, are at least

partially associated with organic phases in coals (Ruch and

others, 1974; Gluskoter and others, 1977; Finkelman, 1980).

Direct multiple-element analysis of whole coals circumvents the long intervals required for ashing, the losses due

to volatilization, and the further exposure of samples to

possible contamination. This paper describes the two directcurrent arc atomic emission spectrographic (DCAES) methods that have produced accurate determinations of 28 elements in the pulverized whole coal (Fletcher and Golightly,

1985). In this study, only 18 elements were determined in 5

Argonne Premium Coals. These methods, which have been

applied principally to the analysis of coal microlithotypes,

offer the basis for efficient, low-cost, multiple-element analysis of whole coals.

EXPERIMENTAL

Approach

A principal difficulty encountered in attempts to arc

small quantities of pulverized coal directly is the rapid evolution of gases that occurs immediately following initiation

of the arc and on the subsequent burning of the organic

phases that remain in a cup-shaped electrode (anode). The

rapidly evolved gases usually blow material from the anode

cup, thus creating uncontrolled losses of the previously

weighed sample, and the erratic flaming of the organic

phase can produce unwanted spectral bands from carbonbased free radicals. These events constitute irreproducible

processes that control the transport of material from the hot

anode cup into the arc discharge. Such severe problems

related to the arcing process have been solved by mixing

powdered coal with a lithium carbonate buffer. This controls

sample transport and excitation conditions in the arc column

and greatly diminishes the possibility for flaming of the hot

coal dissociation products. With these important aspects of

arcing well controlled for coal samples, the methodology

for dc arc spectrographic analysis becomes quite conventional.

Method

Preparation of the Samples

Splits of 100 mg of each whole Argonne Premium

Coal sample, 100 mg of lithium carbonate, and 50 mg of

pure graphite powder were thoroughly mixed and ground

with an agate mortar and pestle to obtain a final homogeneous mixture. For samples that had especially high concentrations of analyte elements, a higher weight ratio of lithium

carbonate to sample was necessary, but the ratio was no

greater than 10:1. Twenty-five milligrams of the final homogeneous mixture was transferred into the appropriate graphite electrode and firmly tamped (Dorrzapf, 1973). These

filled electrodes were dried in an oven at 110 ̊C for 4 hours

immediately before arcing. The drying step was necessary

because it removes water and other readily volatilized com-
14 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

ponents that could cause the loss of sample material from

the anode just after initiation of the arc discharge.

Preparation of Standards

Calibration standards consisted of homogeneous mixtures of oxides and carbonates of the analyte elements in a

lithium carbonate matrix. Dilutions of commercially available standards, which contain 43 elements in lithium carbonate (Spex Industries, Metuchen, New Jersey), provided

calibration standards for the concentration range from 1 to

1,000 μg/g for each element of interest. Individual standards

were diluted on a weight-weight basis with high-purity lithium carbonate (<10 μg/g total impurities).

Reference standards were prepared from the National

Institute of Standards and Technology (NIST), formerly the

National Bureau of Standards (NBS), coal reference materials NIST 1632, NIST 1632a, and NIST 1635 (NBS, 1974,

1978a,b), which were diluted with lithium carbonate in the

same fashion as the samples. Drying and handling of NIST

standards followed the procedure used for samples.

Arcing of Samples and Standards

All samples and standards were arced in an argon-oxygen, or argon, laminar stream that is concentric to the anode

and is introduced through an alumina nozzle arrangement

known as a Helz jet (Helz, 1964). Both the arcing conditions

and the atmosphere were chosen to give complete volatilization of analyte elements from the anode cup into the arc column and to effectively excite those atomic energy levels

giving the spectral lines listed in table 1, without causing

high spectral background. For the volatile elements (group

II, table 1), the objective was to vaporize and to excite these

elements over a relatively long interval while distilling

insignificant amounts of matrix elements into the arc column. The present method was one adapted from that of

Annell (1967) for volatile elements in silicate and carbonate

rocks. For elements in chemical forms that exhibit low volatility (group I, table 1), total vaporization of each sample

into the arc column was necessary for an accurate determination.

Complete details on the spectrographic equipment and

the conditions for arcing samples and for making the necessary measurements are given in table 2. Maintaining a 4-

mm gap between the tips of the electrodes was essential to

the achievement of the accuracy and precision that this

approach is capable of producing.

ACCURACY AND PRECISION

The accuracy of analysis by DCAES is dependent on

the successful element-by-element calibrations of an instrument with standard materials that closely resemble the

materials to be analyzed. For coals, the effective matrix of

the “arced sample” was modified through the use of a lithium carbonate buffer. This modification of the sample

matrix made the arced sample resemble the lithium carbonate matrix of the Spex calibration standards. The quantity of

lithium carbonate relative to that of the sample was sufficient to control the fusion, vaporization, transport, and excitation processes. The concentration ranges for the elements

Table 1. Wavelengths, spectral lines, and determination limits

for elements that can be determined by the direct-current arc

atomic emission spectrography described in this paper. 

1Wavelength and spectrum are from the NIST Wavelength Tables (Meggers and others, 1975). I line emitted by normal atom; II line emitted by

singly ionized atom.

2Lower and upper limits for each element are in units of weight percent.

Element Wavelength,

(nm)1 Spectrum1 Determination

limits (%)2

Group I, involatile elements

Al........................... 265.248 I 0.01–2.0

266.039 I .01–2.0

B............................ 249.773 I .005–.1

Ba .......................... 455.403 II .002–.05

Ca .......................... 315.887 II .01–3

422.673 I .005–.01

Co.......................... 345.350 I .0002–.05

Cr........................... 302.156 I .002–.2

425.435 I .0002–.02

Cu.......................... 327.396 I .0002–.02

Fe........................... 259.837 II .05–3

302.107 I .002–1.0

Mg......................... 277.983 I .01–0.2

285.213 I .0002–.02

Mn......................... 279.482 I .0002–.1

279.827 I .0002–.2

Mo......................... 317.035 I .0005–.2

Nb.......................... 316.340 II .002–.1

Ni........................... 305.082 I .002–.1

341.476 I .0002–.05

349.296 I .01–.2

Si ........................... 251.920 I .2–4

Ti ........................... 308.940 II .002–.2

316.257 II .005–.2

V............................ 318.341 I .0005–.1

Zr........................... 327.926 II .001–.2

Group II, volatile elements

Ag.......................... 338.289 I .0002–.02

As .......................... 278.020 I .02–.2

Bi........................... 306.772 I .0002–.005

Cd.......................... 326.106 I .0002–.1

Ga.......................... 294.364 I .0002–.05

Ge.......................... 265.118 I .0005–.05

303.906 I .0002–.005

Hg.......................... 253.652 I .002–.1

Pb .......................... 283.306 I .0002–.01

Sn .......................... 317.505 I .0002–.02

Tl........................... 276.787 I .0002–.02

Zn .......................... 334.502 I .001–.05
QUANTITATIVE DIRECT-CURRENT ARC ATOMIC EMISSION SPECTROGRAPHY 15

determined by the dc arc spectrographic methods described

in this work are summarized in table 1. Elements exhibiting

the largest deviations are aluminum, calcium, manganese,

and silicon. Experience in the analyses of other coals, vitrinites, exinites, and inertinites indicates that the deviations for

the elements observed here are random, rather than systematic. Measurement errors for the spectrographic method for

concentrations well above (>5 times) the determination limits are typically ±20 percent, and the precision of the

method is ±10 percent.

RESULTS AND DISCUSSION

Only five of the eight Argonne Premium Coals were

available for analysis when this method was developed.

Because this method is labor intensive and the accuracy and

precision for this method at the detection limits for a majority of the elements are no better than the other methods

implemented in the analysis of these coals, the analyses of

the other three coals were not carried out.

Only 18 elements were determined in the 5 whole

Argonne Premium Coals. The results of these analyses are

Table 2. Equipment and operating conditions for direct-current arc atomic emission spectrography.

[A, ampere; ASTM, American Society for Testing and Materials; dc, direct current; min, minute; s, second; T, transmission; V, volt] 

Subject Group I, involatile elements Group II, volatile elements

Sample.................................... 100 mg pulverized whole coal mixed with 100 mg 

Li2CO3 powder (American Potash) and 50 mg 

graphite powder (-200 mesh, Ultra Carbon); 25 

mg of mixture tamped into anode cup.

100 mg pulverized whole coal mixed with 100 mg 

Li2CO3 powder (American Potash) and 100 mg 

graphite powder (-200 mesh, Ultra Carbon); 50 

mg of mixture tamped into anode cup.

Spectrograph........................... Ebert mounting, 3.4-m focal length, 0.5-nm/mm 

reciprocal linear dispersion in first order.

Grating: 600 grooves/mm, blazed for 300 nm.

Eagle mounting, 3-m focal length, 0.55-nm/mm 

reciprocal linear dispersion in first order.

Grating: 590 grooves/mm, blazed for 300 nm.

Slit .......................................... 25 μm ¥ 2 mm for spectra from standards and samples; 25 μm ¥ 4 mm for spectra from iron arc.25 μm ¥ 2.5 mm for spectra from standards and 

samples; 25 μm ¥ 5 mm for spectra from iron 

arc.

Wavelength range ................... 240–360 nm, first order 250–340 nm, second order.

Illumination ............................ Arc image focused on collimator mirror by a 450-

mm focal length cylindrical quartz lens located at 

the entrance slit.

Arc image focused on grating by a 450-mm focal 

length cylindrical quartz lens located near the 

entrance slit.

Filters...................................... Neutral density, 35% T plus 75% T, for exposures 

of samples and standards. Two-step neutraldensity filter, 40% T: 100% T, for iron arc exposures used in calibration of the photographic 

emulsion.

None for exposures of samples and standards. Twostep neutral-density filter, 50% T: 100% T, for 

iron arc exposure used in calibration of the photographic emulsion.

Electrodes............................... Cathode: Graphite rod (Ultra Carbon no. 5001) 3.2 

mm in diameter and 3.8 cm long .

Anode: Thin-walled graphite electrode (Ultra Carbon no. 1590) 3.6 mm in diameter.

Cathode: Same as for group I.

Anode: Graphite electrode (Ultra Carbon no. 3170) 

5.7 mm in diameter .

Excitation ............................... Arc current: Stepped arc current, 5 A dc for 10 s, 15 

A dc for 95 s, across constant 4-mm arc gap. 

Voltage source of 300 V, open circuit. Electrode 

supporting the sample is the anode.

Atmosphere: 80% Ar, 20% O2; 6.6 L/min through 

Helz jet (Helz, 1964).

Arc current: Stepped arc current, 8 A dc for 10 s, 25 

A for 110 s, across constant 4-mm arc gap. Voltage source of 300 V, open circuit. Electrode supporting the sample is the anode.

Atmosphere: Ar, 6.6 L/min through Helz jet (Helz, 

1964).

Photography ........................... Eastman-Kodak III-0 emulsion on 101- ¥ 254-mm 

glass substrate. Emulsion was processed in 

Eastman-Kodak D-19 developer for 3 min 

(20°C), short stop solution for 30 s, and fixer for 

10 min. Then, the plate was washed in tap water 

for 10 to 20 min, allowed to drain, and dried with 

warm air for 5 min.

Same as for group I elements.

Microphotometry.................... All microphotometry was done by conventional 

methods, such as those described by ASTM 

(ASTM, 1971, p. 79–80).

Same as for group I elements.
16 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

shown in tables 3 and 4. The determination of silver, boron,

and molybdenum required special treatment and preparation

time, and so they were eliminated from the routine for analysis. As, Bi, Cd, Hg, Nb, Sn, and Tl were not determined

because of the nature of the matrix of these particular coals. 

REFERENCES

American Society for Testing and Materials (ASTM), 1971, Methods for emission spectrochemical analysis, general practices,

nomenclature, tentative methods, suggested methods (6th

ed.): Philadelphia, ASTM, 1094 p. 

———1984, ASTM Designation D 3683–83, Trace elements in

coal and coal ash by the atomic absorption method: 1984

Annual Book of ASTM Standards, v. 05.05, Gaseous fuels;

Coal and coke, p. 466–469.

Annell, C.S., 1967, Spectrographic determination of volatile elements in silicates and carbonates of geologic interest using an

argon dc arc: U.S. Geological Survey Professional Paper

575–C, p. C132–C136.

Dorrzapf, A.F., Jr., 1973, Spectrochemical computer analysis—

Argon-oxygen D-C arc method for silicate rocks: U.S. Geological Survey Journal of Research, v. 1, no. 5, p. 559–562.

Table 4. Concentrations (in micrograms per gram) of 11 elements in Argonne Premium Coals determined by direct-current arc

atomic emission spectrography. 

Sample V Cr Ni Cu Zn Ga Co Ge Zr Ba Pb

UF PC-1-1 .............. 38 32 22 20 30 11 5 4 36 88 8

UF PC-1-2 .............. 45 38 29 18 30 11 5 4 29 72 10

UF PC-1-3 .............. 41 26 24 16 40 8 5 3 34 84 6

WY PC-2-1............. 10 8 <10 5 <20 4 <5 <2 <20 200 <2

WY PC-2-2............. 14 6 <10 10 <20 2 <5 <2 <20 260 <2

WY PC-2-3............. 17 8 <10 6 <20 3 <5 <2 <20 300 <2

IL PC-3-1................ 52 54 28 9 250 8 <5 8 22 140 9

IL PC-3-2................ 59 57 35 10 260 5 <5 7 25 120 8

IL PC-3-3................ 44 47 37 9 320 7 <5 12 16 92 6

PITT PC-4-1........... 20 23 13 5 20 6 <5 3 23 66 4

PITT PC-4-2........... 25 27 14 6 30 5 <5 <2 21 72 3

PITT PC-4-3........... 27 21 11 7 30 5 <5 <2 28 60 5

POC PC-5-1............ 16 17 11 18 <20 4 5 <2 25 400 5

POC PC-5-2............ 21 17 11 13 <20 3 5 <2 34 460 4

POC PC-5-3............ 18 14 <10 27 <20 4 5 <2 32 500 5

Table 3. Concentrations (in weight percent) of 7 elements in Argonne Premium Coals determined by directcurrent arc atomic emission spectrography. 

Sample Mg Al Ca Ti Mn Si Fe

UF PC-1-1............... 0.097 2 0.57 0.10 0.0053 3 2

UF PC-1-2............... .10 2 .54 .10 .0059 4 3

UF PC-1-3............... .10 2 .63 .10 .0048 3 2

WY PC-2-1 ............. .20 .47 1 .048 .0010 .80 .34

WY PC-2-2 ............. .20 .54 1 .046 .0016 1.0 .33

WY PC-2-3 ............. .20 .44 1 .038 .0014 .52 .20

IL PC-3-1 ................ .096 2 2 .089 .015 3 2

IL PC-3-2 ................ .099 2 2 .10 .015 4 2

IL PC-3-3 ................ .10 2 1 .086 .017 3 3

PITT PC-4-1 ........... .045 1 .24 .086 .0016 2 1

PITT PC-4-2 ........... .048 2 .34 .090 .0028 3 1

PITT PC-4-3 ........... .052 2 .28 .097 .0018 2 2

POC PC-5-1 ............ .079 .80 .69 .084 .0016 .83 .60

POC PC-5-2 ............ .074 .92 .93 .084 .0024 1.0 .80

POC PC-5-3 ............ .079 .84 .79 .078 .0017 .80 .68
QUANTITATIVE DIRECT-CURRENT ARC ATOMIC EMISSION SPECTROGRAPHY 17

Finkelman, R.B., 1980, Modes of occurrence of trace elements in

coal: College Park, Md., University of Maryland, Ph.D. dissertation.

Fletcher, J.D., and Golightly, D.W., 1985, The determination of 28

elements in whole coal by direct-current arc spectrography:

U.S. Geological Survey Open-File Report 85–204, 14 p.

Gluskoter, H.J., Ruch, R.R., Miller, W.G., Cahill, R.A., Dreher,

G.B., and Kuhn, J.K., 1977, Trace elements in coal—Occurrence and distribution: Illinois State Geological Survey Circular 499, 154 p.

Helz, A.W., 1964, A gas jet for D-C arc spectroscopy: U.S. Geological Survey Professional Paper 475–D, p. D176–D178.

Meggers, W.F., Corliss, C.H., and Scribner, B.F., 1975, Tables of

spectral line intensities, Part 1—arranged by elements (2d

ed.): Washington, D.C., National Bureau of Standards Monograph 145, 387 p.

National Bureau of Standards, 1974, National Bureau of Standards

certificate of analysis, standard reference material 1632, trace

elements in coal (bituminous): Washington, D.C., National

Bureau of Standards, 2 p.

———1978a, National Bureau of Standards certificate of analysis, standard reference material 1632a, trace elements in coal

(bituminous): Washington, D.C., National Bureau of Standards, 2 p.

———1978b, National Bureau of Standards certificate of analysis, standard reference material 1635, trace elements in coal

(subbituminous): Washington, D.C., National Bureau of

Standards, 2 p.

Ruch, R.R., Gluskoter, H.J., and Shimp, N.F., 1974, Occurrence

and distribution of potentially volatile trace elements in

coal—A final report: Illinois State Geological Survey Environmental Geology Notes, no. 72, 96 p.
19

Determination of Major and Trace Elements in 

Eight Argonne Premium Coal Samples (Ash and Whole Coal) by 

X-Ray Fluorescence Spectrometry

By John R. Evans, George A. Sellers, Robert G. Johnson, Davison V. Vivit, and Judy Kent

ABSTRACT

X-ray fluorescence (XRF) spectrometric methods were

used in the analysis of eight Argonne Premium Coal samples. Trace elements (Cr, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba,

La, and Ce) in both coal ash and whole coal were determined by energy-dispersive X-ray fluorescence spectrometry. Major elements (Na, Mg, Al, Si, P, S, K, Ca, Ti, Mn, and

Fe) in coal ash and trace elements (Cl and P) in whole coal

were determined by wavelength-dispersive X-ray fluorescence spectrometry. The experimental XRF methods and

procedures used to determine these major and trace elements are described. 

INTRODUCTION

Energy-dispersive X-ray fluorescence (EDXRF) spectrometry and wavelength-dispersive X-ray fluorescence

(WDXRF) spectrometry are used routinely in the determination of major and trace elements in silicate rocks (Norrish

and Hutton, 1969; Johnson, 1984); however, the analysis of

whole coals by XRF spectrometric techniques is more difficult because of the problem of the very light coal matrix and

the scarcity of reliable coal standards. Because coal ash is

more similar to silicate matrix rocks, EDXRF and WDXRF

techniques developed for silicates can be used for the determination of major and trace elements in coal ash samples. 

The rapidity, sensitivity, accuracy, and precision of Xray fluorescence spectrometric methods are well documented for a wide range of geologic materials (Rose and

others, 1963; Norrish and Hutton, 1969; Johnson, 1984;

Johnson and others, 1986; Johnson and Fleming, 1987;

Evans and Jackson, 1989). Analysis of whole coal by XRF

spectrometric techniques has also proven to be successful in

many studies (Kuhn and others, 1975; Johnson and others,

1989). Therefore, the determinations of major and minor

elements in eight Argonne Premium Coal samples by XRF

spectrometric techniques contributed an important part of

the geochemical data base compiled for these materials.

This study was not intended to include interpretations of the

differences of behavior between various coal ranks of the

samples studied. 

EXPERIMENTAL

Coal Ash—EDXRF

All the Argonne Premium Coal samples were first

ashed at 525 ̊C. This is a lower temperature than prescribed

by the American Society for Testing and Materials (ASTM,

1996) method (750 ̊C); however, our method eliminated all

combustible material while retaining the same or higher

concentrations of volatile material. Sample preparation of

coal ash samples followed procedures described in other

publications (Johnson, 1984; Johnson and others, 1986;

Evans and Jackson, 1989). A Kevex 700 EDXRF spectrometer with a Kevex 8000 analyzer was used to fluoresce coal

ash samples powdered to approximately 100 mesh. These

powders were pressed into cups made of Mylar film (6.35

mm) pulled tightly over an aluminum ring with a Teflon collar. The resultant surface appears to be planar. 

Appropriate secondary targets were used (table 1).

Each sample was fluoresced, and intensity measurements

were determined after making background and spectral

overlap corrections. The ratio of the analyte line intensity to

the secondary target Compton scatter intensity was used in

determining elemental concentrations. The Compton ratio

method corrects for matrix effects, particle size variations,

packing density variations, heterogeneity effects, instruTable 1. Secondary targets used for EDXRF

analysis. 

Element Secondary target

Cr ....................................... Fe

Ni, Cu, Zn ........................... Ge

Rb, Sr, Y, Zr, Nb.................. Ag

Ba, La, Ce ........................... Gd
20 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

mental fluctuations, and other sources of error inherent in

EDXRF determinations.

Trace-element concentrations for coal ash samples

were determined from calibration graphs that were constructed by plotting intensity ratio versus the known concentrations for a selected set of standard reference materials

(Abbey, 1983).

Whole Coal—EDXRF

Whole-coal samples were prepared by using procedures similar to those described for EDXRF analyses of the

coal ash (Johnson, 1984; Johnson and others, 1986; Evans

and Jackson, 1989). All intensity measurements were made

on a Kevex 700 spectrometer with a Kevex 7000 analyzer.

Each whole-coal sample was fluoresced using a secondary

target (table 1). Corrections for background interferences

and spectral line overlaps were made before integration of

the analyte line intensity. Trace elements in whole coal samples were determined by EDXRF by using interelement

influence coefficients calculated from fundamental parameters (Johnson and Fleming, 1987). Characterizations of the

coal samples by other analytical techniques must be made

before trace-element determinations can be obtained with

this method. Even though carbon, hydrogen, nitrogen, and

oxygen constitute the largest percentage of the whole coal,

these elements have very little bearing on absorption and

enhancement effects. Major-element concentrations, as

determined from the coal ash (see the next section, “Coal

Ash—WDXRF”), identify the most important influences on

absorption and enhancement effects necessary to generate

accurate interelement influence coefficients from the fundamental parameters algorithm.

 The complexities of the fundamental parameters algorithms used in this study are beyond the scope of this paper.

Detailed explanations of all equations and variables inherent

in the matrix correction procedures were given by Sherman

(1959), Rousseau (1984a,b), and Johnson and Fleming

(1987). 

The lack of a sufficient number of whole-coal standards and the ultimate degradation over time of these standards are major difficulties involved in the characterization

of coals. For these reasons, it is not possible to construct

routine calibration graphs of standard reference materials

for elements of interest; therefore, we must use the fundamental parameters algorithm. Using this algorithm allows

the investigator to make accurate trace-element determinations in whole coal with as few as one well-characterized

standard. In this study, the National Institute of Standards

and Technology (NIST), formerly the National Bureau of

Standards (NBS), whole-coal reference materials, NIST

1632a and NIST 1632b (NBS, 1978a, 1985) were used to

calculate pure element intensities. 

Coal Ash—WDXRF

The fusion method was used to produce glass disks of

coal ash samples (Johnson and others, 1989). This method

eliminates the need for matrix correction routines, since the

significant dilution of the sample by the flux corrects for

heterogeneity effects, particle size variations, and other

sources of error from instrumental fluctuations. A sample/

flux ratio is chosen to yield linear calibration curves over the

range of concentrations found in both samples and standards, without the use of a heavy absorber, such as La2O3.

This sample/flux ratio is needed because of the low final

concentrations of sample components in the sample/flux

mix. 

A 1:9 dilution of sample to flux is obtained by mixing

0.600 g of the coal ash with 5.400 g of a 2:1 mixture of lithium tetraborate to lithium metaborate. This mixture is carefully transferred to a platinum-gold crucible, and three

drops of a 15 percent hydrobromic acid solution are added

as a wetting agent. An automatic Claisse fluxer is used to

heat/mix the sample to temperatures reaching 1,200 ̊C for

approximately 20 minutes. After the sample cools to room

temperature, a thin glass disk with a planar analytical surface is produced, which is adequate for WDXRF analysis.

Elemental intensity measurements are made on a Diano

XRD-8300 wavelength-dispersive X-ray fluorescence spectrometer. 

Standards used in the construction of calibration

graphs were silicate matrix materials selected from those

tabulated by Abbey (1983). Because the coal ash matrix

closely resembles silicate materials in composition, calibration graphs obtained from silicate standard reference materials are reliable for major-element determinations in coal

ash. Standards are prepared for WDXRF analysis in a manner identical to that described above. Calibration graphs

were constructed by plotting the analyte intensity with the

known concentration for a selected set of standard reference

materials for each element of interest. The intensities for the

major elements in the coal ash samples were then used in

the individual calibration graphs. 

A set of synthetic silicate standards was spiked with

sulfur before fusion because the chemical matrix of typical

silicate rock standards does not have sulfur concentrations

similar to those in the coal ash matrix. Because some sulfur

is volatilized during fusion, a portion of the fused standard

was analyzed by a LECO sulfur analyzer to determine the

actual sulfur concentration in the standard. The sulfur determinations of the standards were used to prepare calibration

graphs like those described above for the silicate matrix

materials tabulated by Abbey (1983). 

Whole Coal—WDXRF (Determination of Cl and P)

Briquettes of the whole-coal samples were produced

by mixing 0.500 g of the coal with 0.500 g of microgranular
X-RAY FLUORESCENCE SPECTROMETRY 21

cellulose for 10 minutes on a shaker mill and subsequently

pressing the mixture against a fibrous cellulose backing at

276 MPa for approximately 30 seconds (Johnson and others, 1989). 

The difficulties experienced in the analysis of whole

coals by EDXRF also apply for WDXRF. Reliable wholecoal standard reference materials are scarce. Because these

standards are not commercially available, synthetic standards as well as coal samples characterized by other laboratories were used. Only three NIST coal standards were used

in this study: NIST 1633, 1633a, and 1635 (NBS, 1975,

1979, and 1978b). Spiked graphite samples with varying

concentrations of chlorine and phosphorus served as the

synthetic whole-coal standards. All standards were prepared

identically to those for the whole-coal samples. Intensity

measurements for chlorine and phosphorus were made on a

Diano XRD-8300 wavelength-dispersive X-ray fluorescence spectrometer. 

Calibration graphs were constructed by plotting the

analyte intensity versus the known concentration for a set of

standards. The intensities for chlorine and phosphorus in the

whole-coal samples were then used to calculate chlorine

and phosphorus concentrations from the regression curves.

RESULTS AND DISCUSSION

In this study, eight Argonne Premium Coal samples

were analyzed by EDXRF and WDXRF spectrometry.

Determinations of major oxides in coal ash are detailed in

table 2; trace elements in coal ash in table 3; chlorine and

phosphorus oxide in whole coal in table 4; and trace elements in whole coal in table 5. The precision and accuracy

for the analysis of coal ash samples by EDXRF and

WDXRF closely approximate the precision and accuracy

for the analysis of silicates. A study by Johnson and others

(1989) estimated an average relative difference of ±2 to ±5

percent for WDXRF determinations of major elements (Na,

Mg, Al, Si, P, S, K, Ca, Ti, Mn, and Fe) in coal ash samples.

Trace-element determinations (Cr, Ni, Cu, Zn, Rb, Sr, Y,

Zr, Nb, Ba, La, and Ce) by EDXRF for silicate rocks were

estimated to have an accuracy of <±5 percent for the ratiocalibration graph method (Johnson, 1984). This level of

accuracy is also expected for EDXRF trace-element determinations on coal ash. 

The precision and accuracy of the EDXRF and

WDXRF analyses of whole-coal samples were more difficult to estimate, since a wide range of acceptable standards

Table 2. Major-oxide concentrations (in weight percent) in coal ash determined by WDXRF (reported on an ash basis).

[nd, not determined] 

Coal sample Na2O MgO Al2O3 SiO2 P2O5 SO3 K2O CaO TiO2 MnO Fe2O3

UF PC-1-1 .............. 0.3 1.0 21.6 41.9 0.1 1.0 2.4 4.1 1.0 <0.1 21.0

UF PC-1-2 .............. .2 1.0 21.6 42.7 .1 nd 2.5 4.2 1.0 <.1 19.9 

UF PC-1-3 .............. nd nd nd nd nd nd nd nd nd nd nd

WY PC-2-1............. 1.6 4.9 15.0 31.0 .7 6.4 .4 18.1 1.0 <.1 5.6 

WY PC-2-2............. 1.3 5.2 14.9 31.5 .7 9.9 .4 18.9 1.0 <.1 5.4 

WY PC-2-3............. nd nd nd nd nd nd nd nd nd nd nd

IL PC-3-1................ 1.1 .9 14.1 40.2 .1 4.0 1.5 7.8 .7 <.1 23.9 

IL PC-3-2................ .8 .9 14.0 40.2 .1 3.6 1.5 7.7 .7 <.1 23.8 

IL PC-3-3................ nd nd nd nd nd nd nd nd nd nd nd

PITT PC-4-1........... .6 .6 20.3 45.4 .2 2.0 1.5 3.1 1.1 <.1 22.6

PITT PC-4-2........... .4 .6 20.0 45.8 .2 1.9 1.5 3.0 1.1 <.1 22.2 

PITT PC-4-3........... nd nd nd nd nd nd nd nd nd nd nd

POC PC-5-1............ 1.9 2.1 19.6 32.7 .1 6.6 .7 11.7 1.2 <.1 14.0

POC PC-5-2............ 1.8 2.1 19.5 32.2 .1 6.0 .7 11.7 1.2 <.1 14.1 

POC PC-5-3............ nd nd nd nd nd nd nd nd nd nd nd

UT PC-6-1.............. 3.8 1.4 15.2 41.5 .1 8.3 .6 12.2 .8 <.1 9.0

UT PC-6-2.............. nd nd nd nd nd nd nd nd nd nd nd

UT PC-6-3.............. nd nd nd nd nd nd nd nd nd nd nd

WV PC-7-1............. .3 .7 30.8 54.0 .1 .7 2.9 .4 2.1 <.1 2.8

WV PC-7-2............. nd nd nd nd nd nd nd nd nd nd nd

WV PC-7-3............. nd nd nd nd nd nd nd nd nd nd nd

ND PC-8-1.............. 7.1 7.3 9.0 17.3 .4 20.5 .4 22.6 .3 .1 6.7

ND PC-8-2.............. nd nd nd nd nd nd nd nd nd nd nd

ND PC-8-3.............. nd nd nd nd nd nd nd nd nd nd nd
22 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 3. Trace-element concentrations (in micrograms per gram, μg/g) in coal ash determined by EDXRF (reported on an ash basis).

[nd, not determined] 

Coal sample Cr Ni Cu Zn Rb Sr Y Zr Nb Ba La Ce

UF PC-1-1............... 186 104 146 162 160 440 74 205 20 380 52 112

UF PC-1-2............... 196 118 152 142 154 450 72 196 16 405 60 136

UF PC-1-3............... 196 84 158 150 158 450 84 205 20 370 70 130

WY PC-2-1 ............. 86 50 142 114 40 3,100 40 260 14 3,200 <30 72

WY PC-2-2 ............. 96 46 158 130 40 3,000 42 275 12 3,300 <30 50

WY PC-2-3 ............. 108 44 154 130 44 3,100 44 265 10 3,100 <30 <30

IL PC-3-1 ................ 265 88 66 984 90 188 30 146 12 465 <30 42

IL PC-3-2 ................ 265 122 58 737 90 178 20 130 <10 460 <30 52

IL PC-3-3 ................ 270 120 54 750 92 188 26 136 14 455 <30 40

PITT PC-4-1............ 200 98 70 92 102 760 56 225 22 370 <30 80

PITT PC-4-2............ 190 96 66 92 94 740 56 230 20 410 50 108

PITT PC-4-3............ 195 112 66 88 100 710 48 215 20 385 46 104

POC PC-5-1 ............ 235 132 240 82 50 2,100 134 320 16 3,200 3 100

POC PC-5-2 ............ 225 146 245 100 40 2,100 126 315 16 3,600 50 162

POC PC-5-3 ............ 235 150 225 88 42 2,100 130 320 16 3,500 44 168

UT PC-6-1............... nd nd nd nd nd nd nd nd nd nd nd nd

UT PC-6-2............... nd nd nd nd nd nd nd nd nd nd nd nd

UT PC-6-3............... nd nd nd nd nd nd nd nd nd nd nd nd

WV PC-7-1 ............. 238 91 130 64 218 393 110 412 40 567 75 145

WV PC-7-2 ............. 234 83 115 57 232 402 99 411 43 577 91 163

WV PC-7-3 ............. 237 87 120 59 224 411 118 421 46 552 96 154

ND PC-8-1 .............. 26 25 36 61 nd 6,700 nd 68 <10 5,000 nd nd

ND PC-8-2 .............. 28 17 35 54 nd 6,700 nd 74 <10 4,900 nd nd

ND PC-8-3 .............. 29 19 34 55 nd 6,700 nd 47 <10 4,700 nd nd

Table 4. Chlorine and phosphorus oxide concentrations (in weight percent) in whole

coal determined by WDXRF. 

Coal sample Cl P2O5 Coal sample Cl P2O5

UF PC-1-1 .............. 0.15 <0.01 POC PC-5-1............ 0.16 <0.01

UF PC-1-2 .............. .14 <.01 POC PC-5-2............ .16 <.01

UF PC-1-3 .............. .15 <.01 POC PC-5-3............ .16 <.01

WY PC-2-1............. <.01 .06 UT PC-6-1.............. <.01 <.01

WY PC-2-2............. <.01 .05 UT PC-6-2.............. <.01 <.01

WY PC-2-3............. <.01 .06 UT PC-6-3.............. <.01 <.01

IL PC-3-1................ .05 <.01 WV PC-7-1............. .04 <.01

IL PC-3-2................ .05 <.01 WV PC-7-2............. .04 <.01

IL PC-3-3................ .06 <.01 WV PC-7-3............. .05 <.01

PITT PC-4-1........... .06 .02 ND PC-8-1.............. <.01 .04

PITT PC-4-2........... .06 .02 ND PC-8-2.............. <.01 .04

PITT PC-4-3........... .07 .02 ND PC-8-3.............. <.01 .04
X-RAY FLUORESCENCE SPECTROMETRY 23

was not available. However, Johnson and others (1989) estimated the average relative difference for chlorine and phosphorus oxide determinations on whole coals to be ±10

percent. Trace-element (Cr, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb,

Ba, La, and Ce) determinations on the whole coal by

EDXRF generally show close agreement (±10 percent)

between replicate samples. A wide variance was noted,

however, when the whole-coal trace-element results were

compared with the results obtained on the coal ash. Further

investigation is needed to evaluate more clearly the accuracy

of the matrix correction method for whole coals. 

REFERENCES

Abbey, Sydney, 1983, Studies in “standard samples” of silicate

rocks and minerals, 1969–1982: Canada Geological Survey

Paper 83–15, 114 p. 

American Society for Testing and Materials (ASTM), 1996,

ASTM Designation D 3174–93, Standard test method for ash

in the analysis sample of coal and coke from coal: 1996

Annual Book of ASTM Standards, v. 05.05, Gaseous fuels;

Coal and coke, p. 291–294.

Evans, J.R., and Jackson, J.C., 1989, Determination of tin in silicate rocks by energy-dispersive X-ray fluorescence spectrometry: X-Ray Spectrometry, v. 18, p. 139–141.

Johnson, R.G., 1984, Trace element analysis of silicates by means

of energy-dispersive X-ray spectrometry: X-Ray Spectrometry, v. 13, no. 2, p. 64–68.

Johnson, R.G., and Fleming, S.L., II, 1987, Energy-dispersive Xray fluorescence analysis of massive sulfides using fundamental influence coefficients: X-Ray Spectrometry, v. 16, p. 167–

170.

Johnson, R.G., Palmer, C.A., Dennen, K.O., and Hearn, P.P., 1986,

Energy-dispersive X-ray fluorescence analysis of trace elements in carbonate rocks: Applied Spectroscopy, v. 40, no. 1,

p. 76–79.

Johnson, R.G., Sellers, G.A., and Fleming, S.L., II, 1989, The

determination of major and minor elements in coal ash and of

chlorine and phosphorus in whole coal by X-ray fluorescence

spectrometry, in Golightly, D.W., and Simon, F.O., eds.,

Methods for sampling and inorganic analysis of coal: U.S.

Geological Survey Bulletin 1823, p. 35–39.

Kuhn, J.K., Harfst, W.F., and Shimp, N.F., 1975, X-ray fluorescence analysis of whole coal, in Babu, S.P., ed., Trace elements in fuel: Washington, D.C., American Chemical Society,

p. 66–73.

Table 5. Trace-element concentrations (in micrograms per gram, μg/g) in whole coal determined by EDXRF.

[nd, not determined] 

Coal sample Cr Ni Cu Zn Rb Sr Y Zr Nb Ba La Ce

UF PC-1-1 .............. 15 27 20 35 23 61 nd 24 nd 54 31 27

UF PC-1-2 .............. 23 22 18 32 21 63 nd 22 nd 68 9 46

UF PC-1-3 .............. 19 21 17 31 20 61 nd 24 nd 59 9 48

WY PC-2-1............. 3 9 18 26 14 292 nd 19 nd 404 4 18

WY PC-2-2............. 5 7 17 29 14 300 nd 21 nd 407 4 21

WY PC-2-3............. nd 8 17 21 11 291 nd 17 nd 415 11 35

IL PC-3-1................ 29 33 15 137 22 33 nd 24 nd 112 16 23

IL PC-3-2................ 36 30 13 105 17 30 nd 22 nd 122 15 39

IL PC-3-3................ 41 33 15 186 21 35 nd 24 nd 129 15 64

PITT PC-4-1........... 6 17 10 17 8 59 nd 15 nd 46 23 19

PITT PC-4-2........... 10 11 9 14 8 61 nd 17 nd 22 1 25

PITT PC-4-3........... 9 15 10 15 8 69 nd 18 nd 19 2 6

POC PC-5-1............ 5 11 16 14 5 86 nd 10 nd 134 1 4

POC PC-5-2............ 7 9 16 14 4 77 nd 8 nd 124 4 19

POC PC-5-3............ 4 12 19 15 5 93 nd 11 nd 164 10 8

UT PC-6-1.............. <10 5 8 <2 3 58 2 20 <10 28 9 20

UT PC-6-2.............. <10 5 8 <2 2 65 <2 17 <10 32 9 13

UT PC-6-3.............. <10 5 8 <2 3 66 <2 16 <10 28 11 12

WV PC-7-1............. 50 17 30 9 43 87 19 106 13 230 15 64

WV PC-7-2............. 48 18 30 10 43 87 20 102 <10 202 18 54

WV PC-7-3............. 48 19 32 10 40 83 17 101 13 200 14 48

ND PC-8-1.............. <10 4 8 5 4 800 <2 20 <10 1000 8 21

ND PC-8-2.............. <10 10 10 4 5 802 <2 19 <10 1040 6 19

ND PC-8-3.............. <10 4 10 6 3 753 <2 17 <10 1060 10 17
24 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

National Bureau of Standards, 1975, National Bureau of Standards

certificate of analysis, standard reference material 1633, trace

elements in coal fly ash: Washington, D.C., National Bureau

of Standards, 2 p.

———1978a, National Bureau of Standards certificate of analysis,

standard reference material 1632a, trace elements in coal

(bituminous): Washington, D.C., National Bureau of Standards, 2 p.

———1978b, National Bureau of Standards certificate of analysis, standard reference material 1635, trace elements in coal

(subbituminous): Washington, D.C., National Bureau of

Standards, 2 p.

———1979, National Bureau of Standards certificate of analysis, standard reference material 1633a, trace elements in

coal fly ash: Washington, D.C., National Bureau of Standards, 2 p.

———1985, National Bureau of Standards certificate of analysis,

standard reference material 1632b, trace elements in coal

(bituminous): Gaithersburg, Md., National Bureau of Standards, 5 p.

Norrish, K., and Hutton, J.T., 1969, An accurate X-ray spectrographic method for the analysis of a wide range of geological

samples: Geochimica et Cosmochimica Acta, v. 33, no. 4, p.

431–453.

Rose, H.J., Jr., Adler, Isidore, and Flanagan, F.J., 1963, X-ray fluorescence analysis of light elements in rocks and minerals:

Applied Spectroscopy, v. 17, no. 4, p. 81–85.

Rousseau, R.M., 1984a, Fundamental algorithm between concentration and intensity in XRF analysis. 1—Theory: X-Ray

Spectrometry, v. 13, no. 3, p. 115–120.

———1984b, Fundamental algorithm between concentration and

intensity in XRF analysis. 2—Practical application: X-Ray

Spectrometry, v. 13, no. 3, p. 121–125.

Sherman, J., 1959, Research note—Simplification of a formula in

the correlation of fluorescent X-ray intensities from mixtures:

Spectrochimica Acta, v. 15, no. 6, p. 466–470.
25

Determination of 29 Elements in 8 Argonne Premium Coal Samples by 

Instrumental Neutron Activation Analysis

By Curtis A. Palmer

ABSTRACT

Twenty-nine elements have been determined in triplicate splits of the eight Argonne Premium Coal samples by

instrumental neutron activation analysis. Data for control

samples NIST (National Institute of Standards and Technology) 1633 (fly ash) and NIST 1632b (bituminous coal) are

also reported. The factors that could lead to errors in analysis of these samples, such as spectral overlaps, low sensitivity, and multiple sources of interfering nuclear reactions, are

discussed.

INTRODUCTION

The U.S. Geological Survey (for example, Zubovic and

others, 1979, 1980; Oman and others, 1981; Currens and

others, 1986, 1987) and other laboratories (for example,

Gluskoter and others, 1977) have used instrumental neutron

activation analysis (INAA) for the determination of major,

minor, and trace elements in thousands of coal samples. The

application of INAA for the analysis of coal has been

described in several papers (for example, Block and Dams,

1973; Ondov and others, 1975; Rowe and Steinnes,

1977a,b; Swaine, 1985; Palmer and Baedecker, 1989). The

analysis of coal by INAA is especially useful because determinations are made on the whole coal in contrast to other

techniques in which the ash is used as the sample matrix.

Therefore, INAA can be used to measure elements that

might be volatilized during ashing, such as bromine. All elements are determined on the same sample split so that element ratios used in understanding geochemical

environments are not affected by inhomogeneities in a coal

sample. In addition, INAA has very low detection limits for

many elements, can be easily automated, and provides precise data for many major, minor, and trace elements.

ACKNOWLEDGMENTS

The author would like to thank Jeff Grossman and Phil

Baedecker for help with the derivation of the fission product

correction formulas, Mike Pickering for assistance in counting the samples, and Jean Kane, Phil Baedecker, and Frank

Walthall for suggestions to the manuscript.

EXPERIMENTAL

Three splits of approximately 500 mg of each of the

eight Argonne Premium Coal samples were weighed and

heat sealed in 1.5-cm3 polyethylene vials. These samples

were irradiated for 8 hours in the TRIGA research reactor

facility of the U.S. Geological Survey in Denver, Colo., at a

neutron flux of 3¥1012 neutrons/cm2 sec. After a delay of 3

days to eliminate or reduce short-lived activity, the samples

were shipped by overnight delivery to laboratories in

Reston, Va., for gamma-ray counting.

The samples were counted at three different times on

high-resolution coaxial germanium and germanium (lithium) detectors for gamma-ray spectroscopy. The first count

was started approximately 4 days after irradiation. A second

count was started at 17 days after irradiation after allowing

the short-lived activities (especially 24Na, half-life=15

hours) to decay, and then a third count was begun approximately 2 months after irradiation to obtain higher precision

on the measurement of the long-lived radionuclides. The

gamma-ray detectors were coupled to multichannel pulseheight analyzers, which are capable of dividing the spectrum into 4,096 energy increments or channels. An automatic sample changer similar to that described by Massoni

and others (1973) was used to change the samples. All spectra were processed by using the computer program

SPECTRA (Baedecker and Grossman, 1989, 1994).

SAMPLES AND STANDARDS

The eight Argonne National Laboratory Premium Coal

samples used in this study have been described previously

(Vorres, 1990). The convention for sample identification is

the same as described by Palmer in the Introduction of this

volume. Three multiple-element standards, NIST (National

Institute of Standards and Technology) 1632a, NIST 1633a,
26 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

and Eastman-Kodak TEG–50–B, and two control samples,

NIST 1633 (fly ash; different from 1633a) and NIST 1632b

(bituminous coal), were included with each irradiation. The

element concentration values for the NIST standards used

for analysis have been reported previously (Palmer and Baedecker, 1989) and are largely based on the results of Ondov

and others (1975).

A comparison of the results of this study with literature

values for the control samples is given in table 1. The analytical errors reported for the control NIST 1632b in this

study are based on counting statistics at the one-sigma level.

NIST certified and information values are shown for NIST

1632b. Our determinations of concentrations in control

1632b agree with all certified values within the stated errors

and generally agree, within 10 percent, with the NIST information values that have no reported errors.

RESULTS AND DISCUSSION

The concentrations and their associated errors based on

counting statistics for 29 elements for each of the Premium

Coal samples are shown in table 2. Iron is the only major

element (concentrations >1 percent) determined, and

sodium and potassium are the only minor elements (concentrations <1 percent, >0.1 percent) determined. All other elements determined are trace elements. For many elements,

the concentration values ranged over a factor of 5 among the

eight Argonne Premium Coal samples.

The errors reported in table 2 are based on counting

statistics only. Generally, the precision of the data based on

the replicate analyses is within the counting errors for

elements where the reported error is greater than 5 percent.

For some elements with small counting errors, the analytical

Table 1. Comparison of concentrations determined (in micrograms per gram, μg/g) from this study with

literature values.

[Concentrations in this study were determined by instrumental neutron activation analysis (INAA). Blank, no values available

from listed source] 

1Values taken from Ondov and others (1975).

2Values taken from NIST (National Institute of Standards and Technology) 1632b Certificate (National Bureau of Standards,

1985). Values with no error listed are NIST information values; all others are NIST certified values.

Element

NIST 1633, fly ash NIST 1632b, bituminous coal

This study Literature1 This study Literature2

Na............. 3,060±64 3,200±400 513±5 515±11

K............... 16,000±640 16,100±1,500 740±37 748±28

Sc.............. 27.3±0.27 27±1 2.060±0.02 1.9

Cr.............. 113.4±8.6 127±6 10.4±0.3 11

Fe.............. 62,600±630 62,000±3,000 7,780±160 7,590±450

Co............. 40.8±2.0 41.5±1.2 2.33±0.04 2.29±0.17

Ni.............. 92±10 98±9 8.1±2 6.1±0.27

Zn ............. 183±9.5 216±25 11.7±1.4 11.89±0.78

As ............. 56.0±1.6 58.0±4 3.80±0.11 3.73±0.09

Se.............. 9.0±0.54 10.2±1.4 1.24±0.10 1.29±0.11

Br.............. 6.5±0.32 12±4 21.3±1.1 17

Rb............. 10±6.3 125±10 4.2±0.76 5.05±0.11

Sr.............. 1,340±67 1,700±300 97±5.8 102

Sb ............. 6.61±0.2 6.9±0.6 .259±0.01 .24

Cs ............. 7.76±0.23 8.6±1.1 .414±0.012 .44

Ba ............. 2,450±74 2,700±200 69±2.8 67.5±2.1

La ............. 80.4±1.6 82±2 4.80±0.01 5.1

Ce ............. 139±2.7 146±15 9.19±0.18 9

Nd............. 55±7.2 57.8±1.6 <12

Sm ............ 14.2±0.3 12.4±0.9 .899±0.009 .87

Eu ............. 2.68±0.08 2.5±0.4 .176±0.004 .17

Tb ............. 1.79±0.054 1.9±0.3 .104±0.003

Yb............. 5.99±0.18 7±3 .366±0.01

Lu ............. 1.12±0.046 1.0±0.1 .099±0.004

Hf ............. 7.12±0.21 7.9±0.4 .410±0.002 .43

Ta.............. 2.03±0.06 1.8±0.3 .194±0.03

W.............. 4.93±0.25 4.6±1.6 .52±0.05 .48

Th ............. 23.1±0.46 24.8±2.2 1.321±0.026 1.342±0.036

U............... 10.7±0.9 12.0±0.5 .42±0.05 .436±0.012
Table 2. Concentrations (in micrograms per gram, μg/g) of 29 elements in Argonne Premium Coal samples. [Concentrations were determined by instrumental neutron activation analysis (INAA). Errors in percent are based on one-sigma counting statistics only]  Element UF PC-1-1 UF PC-1-2 UF PC-1-3 WY PC-2-1 WY PC-2-2 WY PC-2-3 IL PC-3-1 I Na ....... 336±2% 343±2% 342±3% 1,140±2% 1,170±2% 1,130±2% 1,030±2% 1 K......... 2,640±4% 2,620±4% 2,800±5% 268±10% 340±11% 270±17% 1,990±4% 1 Sc........ 4.04±1% 4.01±1% 4.14±1% 1.67±2% 1.69±2% 1.67±1% 2.55±1%  Cr........ 20.4±3% 20.3±3% 20.4±5% 5.7±6% 6.22±4% 6.23±4% 33.7±2%  Fe........ 17,600±1% 18,100±1% 17,900±1% 3,810±2% 3,790±2% 3,390±2% 26,600±1% 26 Co ....... 5.27±2% 5.41±2% 5.31±2% 1.66±3% 1.73±2% 1.65±2% 4.21±6%  Ni........ 15.9±16% 13.2±18% 14.3±19% 4.4±29% 5.4±24% 5.0±24% 24.2±11%  Zn ....... 18.2±8% 17.0±14% 23.9±5% 11.0±4% 11.6±5% 11.2±9% 218±2%  As........ 16.6±3% 17.6±3% 17.1±3% 3.67±3% 3.23±3% 3.75±3% 4.46±4%  Se........ 2.09±8% 1.88±7% 1.8±22% 1.57±11% 1.49±8% 1.63±6% 3.78±4%  Br........ 66±8% 65±8% 66±8% 2.96±8% 2.88±8% 2.79±8% 6.6±8%  Rb ....... 19.4±8% 19.0±8% 20.0±8% <5 <5 <5 15.5±14%  Sr ........ 56±16% 58±19% 33±22% 263±5% 248±5% 245±5% 42±29%  Sb........ .558±5% .50±8% .535±5% .180±6% .203±5% .191±5% .848±3%  Cs........ 1.48±3% 1.52±3% 1.56±3% .163±7% .173±12% .160±11% 1.14±4%  Ba ....... 52±14% 6827±11% 63±15% 324±3% 318±3% 297±3% 94±7%  La........ 10.0±2% 10.0±2% 10.3±3% 5.32±3% 5.34±3% 5.38±3% 6.11± 3%  Ce ....... 18.1±3% 18.2±3% 18.7±2% 9.07±3% 9.5±5% 9.6±5% 12.5±3%  Nd....... <20 <18 8.0±29% <13 <11 <9 <10  Sm ...... 1.98±2% 1.94±2% 2.00±2% .968±2% .988±2% .977±2% 1.19±4% 1 Eu ....... .389±3% .399±3% .406±6% .201±4% .199±4% .195±6% .229±3%  Tb ....... .275±5% .252±4% .260±4% .122±7% .122±4% .115±5% .147±5%  Yb ....... .91±4% .84±5% .90±4% .42±8% .443±5% .40±8% .51±7%  Lu ....... .227±5% .213±5% .220±5% .101±5% .103±5% .098±5% .140±12%  Hf........ .647±4% .660±4% .67±9% .621±3% .622±3% .560±5% .54±8%  Ta........ .207±5% .224±5% .227±5% .141±5% .155±5% .142±7% .188±5%  W ........ 1.00±6% 1.09±7% 1.09±8% .38±10% .36±12% .40±12% 1.53±5%  Th ....... 2.59±2% 2.64±2% 1.547±2% 1.56±3% 1.58±3% 2.01±2% 1.95±2%  U......... .81±8% .81±8% .86±9% .55±10% .54±9% .52±8% 4.46±4% 
Table 2. Concentrations (in micrograms per gram, μg/g) of 29 elements in Argonne Premium Coal samples—Continued. [Concentrations were determined by instrumental neutron activation analysis (INAA). Errors in percent are based on one-sigma counting statistics only] Element PITT PC-4-1 PITT PC-4-2 PITT PC-4-3 POC PC-5-1 POC PC-5-2 POC PC-5-3 UT PC-6-1 UT  Na....... 343±2% 343±3% 344±3% 797±2% 773±2% 778±2% 1,485±2% 1,4 K......... 1,090±5% 1,120±6% 1,090±7% 284±11% 260±14% 330±15% 180±25% <2 Sc........ 2.61±2% 2.56±1% 2.55±1% 1.80±2% 1.79±2% 1.77±1% .832±2% .8 Cr........ 15.0±3% 15.0±3% 14.5±3% 9.3±4% 9.06±3% 8.85±3% 5.25±4% 5. Fe........ 13,600±2% 13,400±2% 13,300±2% 5,040±2% 5,210±2% 5,020±2% 3,270±2% 3,1 Co....... 2.65±3% 2.61±4% 2.60±6% 4.09±2% 4.13±2% 3.98±2% 1.01±2% .9 Ni........ 9.4±21% 11.3±17% <12 9.2±17% 8.5±19% 8.2±19% <3 3 Zn ....... 8.9±4% 7.8±7% 10.5±12% 5.74±5% 6.15±5% 7.3±5% 4.80±5% 7. As ....... 8.44±3% 8.30±3% 8.5±4% 10.43±3% 10.6±3% 9.89±3% .51±7% . Se........ 1.49±7% 1.60±7% 1.34±7% 2.3±28% 2.5±18% 2.601±11% 1.03±10% 1. Br........ 15.7±8% 15.5±8% 15.5±8% 50±8% 50±8% 49±8% 1.14±5 1. Rb....... 9.0±16% 7.2±16% 7.1±16% <6 <6 <3 <2 1. Sr........ 58±12% 61±22% 65±19% 97±23% 116±7% 101±11% 71±7%  Sb ....... .239±6% .240±5% .221±6% .625±4% .458±4% .535±4% 118±7% .0 Cs ....... .737±4% .69±9% .67±8% .256±5% .283±17% .247±11% .123±6% .1 Ba ....... 44±13% 51±11% 44±12% 197±5% 203±5% 193±4% 35.7±8% 38 La ....... 6.19±3% 6.15±3% 6.11±3% 6.78±3% 6.77±3% 6.73±3% 3.41±3% 3. Ce ....... 11.5±3% 11.5±5% 11.1±3% 11.6±3% 11.8±3% 11.5±3% 4.88±3% 4. Nd....... <12 <8 <10 <18 <16 <14 <3 2 Sm ...... 1.100±2% 1.09±2% 1.09±2% 1.23±2% 1.21±2% 1.21±2% .517±3% .5 Eu ....... .221±4% .214±4% .208±6% .243±4% .241±4% .218±10% .100±6% .0 Tb ....... .133±5% .131±10% .132±8% .158±6% .173±4% .169±4% .065±5% .0 Yb....... .478±5% .463±5% .468±5% .555±5% .56±10% .545±5% .204±7% .1 Lu ....... .121±6% .117±10% .120±5% .132±5% .142±5% .132±5% .036±9% .0 Hf ....... .518±4% .49±8% .500±4% .441±6% .429±4% .444±4% .478±3% .4 Ta........ .168±5% .163±5% .165± 5% .117±12% .108±8% .123±6% .060±7% .0 W........ .79±6% .80±8% .76±8% .84±7% .91±8% .77±8% .42±10% . Th ....... 1.53±3% 1.46±3% 1.44±3% 1.19±3% 1.12±8% 1.17±3% .609±3% .6 U......... .36±13% .37±10% .45±11% .47±16% .51±13% .55±13% .76±8% .
Table 2. Concentrations (in micrograms per gram, μg/g) of 29 elements in Argonne Premium Coal samples—Continued.[Concentrations were determined by instrumental neutron activation analysis (INAA). Errors in percent are based on one-sigma counting statistics only]  Element WV PC-7-1 WV PC-7-2 WV PC-7-3 ND PC-8-1 ND PC-8-2 ND PC-8-3 Na ....... 460 ±10% 351±3% 352±2% 5,400±2% 5,330±3% 5,150±2% K ......... 5,170 ±3% 4,970±6% 5,000±4% 280±28% <400 300±16% Sc........ 7.69 ±1% 7.54±1% 7.61±1% .846±2% .828±2% .865±3% Cr........ 36.2 ±1% 35.6±2% 35.7±2% 2.23±5% 2.16±5% 2.33±5% Fe........ 4,040 ±3% 3,840±2% 4,080±2% 5,530±2% 5,290±2% 5,630±4% Co ....... 7.65 ±2% 7.91±2% 7.72±3% .771±3% .761±3% .802±3% Ni........ 13.0 ±20% 18±20% 13.1±19% <6 <3 <3 Zn ....... 14.0 ±4% 12.5±4% 14.0±4% 5.71±5% 5.5±7% 5.86±5% As........ 5.8 ±12% 5.29±3% 7.40±3% 2.67±4% 2.61±4% 2.61±4% Se........ 5.3 ±7% 5.54±5% 5.5±7% .51±18% .61±15% .63±14% Br........ 16.9 ±2% 16.9±3% 16.9±3% 1.49±6% 1.34±6% 1.43±6% Rb ....... 29.8 ±3% 28.5±3% 31.2±4% .36±30% .99±26% <1 Sr ........ 60 ±11% 73±19% 58±17% 628±4% 580±9% 583±5% Sb........ .521 ±2% .540±3% .502±4% .148±7% .155±8% .158±9% Cs........ 1.88 ±2% 1.87±2% 1.84±3% .072±10% .097±23% .089±9% Ba ....... 166 ±11% 116±5% 116±6% 699±4% 660±4% 671±3% La........ 21.7 ±2% 21.6±2% 21.3±2% 2.79±3% 2.84±3% 2.84±3% Ce ....... 36.0 ±2% 35.2±3% 36.1±2% 4.34±3% 4.33±3% 4.68±5% Nd ....... 12.4 ±8% 11.0±7% 12.4±9% <3 2.1±25% 2.5±22% Sm....... 3.56 ±2% 3.50±2% 3.51±2% .420±3% .419±3% .388±3% Eu ....... .674 ±2% .651±2% .697±4% .079±4% .077±4% .087±4% Tb........ .408 ±2% .390±2% .402±3% .052±9% .052±15% .063±7% Yb ....... 1.69 ±3% 1.61±7% 1.52±5% .317±9% .298±10% .245±6% Lu ....... .202 ±3% .194±5% .191±6% .039±13% .035±9% .035±8% Hf........ 1.88 ±2% 1.80±2% 1.80±2% .342±4% .341±3% .340±4% Ta ........ .675 ±2% .617±3% .630±5% .095±6% .088±5% .095±5% W ........ 1.33 ±7% 1.19±8% 2.53±4% .38±17% .25±31% .43±13% Th........ 6.49 ±2% 6.26±3% 6.49±3% 1.057±2% 1.027±2% 1.113±2% U ......... 1.67 ±5% 1.60±7% 1.64±8% .52±16% .46±1% <.2
30 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

precision is poorer because of the other sources of error

such as sample homogeneity or positioning during counting.

Errors reported in table 2 were generally less than 10

percent except for nickel, rubidium, and neodymium, in

which the concentration was near or below the detection

limit for all samples. Errors were also greater than 10 percent for barium in UF PC-1; uranium in PITT PC-4, POC

PC-5, and ND PC-8; and ytterbium in UT PC-6 (table 2).

Errors reported for potassium are variable even at the same

concentration because it has the shortest half-life of the

elements determined in this study, and the detection limit

varies by nearly an order of magnitude during the 2-day

counting cycle for the entire sample set. 

In table 2, the concentrations reported for nickel in WY

PC-2 and UT PC-6 and for rubidium in UT PC-6 and ND

PC-8 are actually below the expected detection limits given

in table 3 because the values in table 3 are determined for a

“typical” coal matrix. The detection limits for individual

coal samples may change because of variations in the concentrations of the most sensitive elements that dominate the

gamma-ray spectrum and because of variations in the intensities of spectral interferences. The percent correction of

each spectral interference for all premium coals is given in

table 4. Generally, only a small correction is needed for

most elements. Some elements, such as nickel, selenium,

and samarium in some samples, require changes larger than

10 percent. 

In addition to corrections made because of spectral

interferences, barium and the light rare earth elements lanthanum, cerium, neodymium, and samarium were corrected

Table 3. Long-lived (>10 hours) radionuclides.

[Table modified from Palmer and Baedecker (1989). d, day; h, hour; yr, year; mg/g, micrograms per gram] 

Element Indicator 

radionuclide Half-life Preferred gamma (g) energy

Limit of 

determination

(μg/g except % 

as indicated)

Potential spectral interferences

Radionuclide Energy Radionuclide Energy

Na................ 24Na 15.0 h 1,368.9 10

 2,753.9

K.................. 42K 12.4 h 1,524.7 .01%

Sc................. 46Sc 84 d 1,120.5 .01

Cr................. 51Cr 27.8 d 320.1 .5 177Lu 321.3 147Nd 319.4

Fe................. 59Fe 45.6 d 1,099.3 50 182Ta 1,289.1

 1,291.5 75

Co................ 60Co 5.3 yr 1,173.2 .2

 1,332.5

Ni................. 58Co 71.3 d 810.8 .55 152Eu 810.8

Zn ................ 65Zn 245 d 1,115.4 1 160Tb 1,115.1

As ................ 76As 26.4 h 559.0 .1

Se................. 75Se 120.0 d 264.6 1 182Ta 264.1

Br................. 82Br 35.4 h 554.3 .5

 776.5 .5

Rb................ 86Rb 18.7 d 1,076.8 5

Sr................. 85Sr 64.0 d 514.0 50

Sb ................ 122Sb 67.2 h 564.0 .05 124Sb 60.0 d 1,691.0 .1

Cs ................ 134Cs 2.1 yr 795.8 .1

Ba ................ 131Ba 12.0 d 476.3 50

La ................ 140La 40.2 h 1,596.6 .02

 487.0 .05

Ce ................ 141Ce 32.5 d 145.4 .5 154Eu 145.6

Nd................ 147Nd 11.1 d 531.0 2

Sm ............... 153Sm 46.8 h 103.2 .5 239Np 103.7

Eu ................ 152Eu 12.7 yr 779.1 .04

 1,408.1 .01

Tb ................ 160Tb 72.1 d 298.6 .05 233Pa 299.9

 1,178.1 .1

Yb................ 175Yb 101.0 h 396.1 .1 147Nd 398.2 233Pa 398.2

 282.6 .2

Lu ................ 177Lu 6.7 d 208.4 .01 239Np 209.7

Hf ................ 181Hf 42.5 d 482.2 .1

 133.1 .05

Ta................. 182Ta 115.1 d 1,221.3 .02

 1,189.2 .03

W................. 187W 24.0 h 479.5 .1

 685.7 .1 147Nd 685.9

Th ................ 233Pa 27.0 d 311.9 .1

U.................. 239Np 2.3 d 277.6 .5
INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS 31

for interference because of neutron-induced fission of 235U;

table 5 shows the percent correction for these elements.

However, corrections for barium and lanthanum are time

dependent and therefore vary during the counting of the

samples. The concentration of barium, Bacorr (corrected for

the time-dependent fission correction factor), was calculated

by using the formula:

Bacorr = Bameas-2.9Ue0.0402t

and the concentration of lanthanum, Lacorr (corrected for the

time-dependent fission correction factor), was calculated by

using:

Lacorr = Lameas-0.002723Ue0.3592t

where t = time after bombardment in days, Bameas and Lameas

are the uncorrected barium and lanthanum concentrations,

and U is the concentration of uranium. The constant

0.002723 in the La equation is calculated by assuming a

235U cross section of 580 barns, which agrees with the experimental data within ±1 percent. The half-lives for 131Ba and 239Np (U) and 140La were taken from table 3. The half-life of 140Ba, which decays to the measured 140La, was assumed to

be 12.8 days. The fission correction factors are generally

quite small except for barium and cerium in IL PC-3, which

are about 16 and 8 percent, respectively, and for barium and

Table 5. Average percent correction made for fission product interferences during INAA

(instrumental neutron activation analysis) of eight Argonne Premium Coal samples.

[Apparent concentration of each fission product is given in micrograms per gram (μg/g) per μg/g of U. <0.1

indicates a correction of less than 0.1 percent was made. Data for individual splits have been reported by

Palmer (1991)] 

1Apparent concentration of element in μg/g per μg/g of U is time dependent.

2Correction made on upper limit value.

Fission product......................

Apparent concentration.........

131Ba

(

1)

140La

(

1

)

141Ce

0.27

147Nd

 0.17

153Sm

0.00008

UF PC-1 ........................... 4.9 0.1 1.2 20.6 <0.1

WY PC-2.......................... .6 .2 1.5 2.8 <.1

IL PC-3............................. 16.1 1.0 8.2 26.8 <.1

PITT PC-4 ........................ 3.4 .1 .9 2.7 <.1

POC PC-5......................... .9 .1 1.2 2.5 <.1

UT PC-6 ........................... 7.1 .4 4.0 25.0 <.1

WV PC-7.......................... 3.8 .1 1.3 2.2 <.1

ND PC-8........................... .1 .3 2.7 22.9 <.1

Table 4. Average percent corrections made for spectral interferences on counts with the lowest errors during INAA (instrumental

neutron activation analysis) of eight Argonne Premium Coal samples.

[— indicates no correction was made; <0.1 indicates an extremely small correction was made. No corrections were required for spectral interference of the 160Tb line by the 233Pa line in any of these samples. Data for individual splits have been reported by Palmer (1991)] 

Element ...........................

Interfering

radionuclide.................

Cr

177Lu

and (or)

147Nd

 Fe

182Ta

Ni

152Eu

Zn

160Tb

Se

182Ta

Ce

154Eu

Sm

239Np

Yb

147Nd

and (or)

233Pa

Lu

239Np

W

147Nd

UF PC-1 ..................... 2.3 <0.1 10.5 3.3 14.5 0.2 4.5 0.3 3.0 0.4

WY PC-2.................... 4.8 .2 142 2.7 13.1 .5 5.4 .4 5.3 —

IL PC-3....................... 1.2 <.1 4.5 .2 7.5 — 26.5 1.5 — .6

PITT PC-4 .................. 1.7 <.1 7.8 4.0 14.2 .4 3.9 .4 3.8 .4

POC PC-5................... 2.5 <.1 10.0 6.2 7.8 .3 3.5 .6 3.1 —

UT PC-6 .................... 1.7 .1 12.3 2.1 10.9 — 9.7 .4 1.3 .7

WV PC-7.................... 1.5 .5 14.8 6.3 13.5 .3 3.0 .6 — 1.7

ND PC-8..................... 4.4 <.1 9.6 2.3 22.2 — 8.9 .5 — —
32 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

neodymium in UT PC-6, which have correction factors as

high as 7 and 5 percent, respectively.

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Baedecker, P.A., and Grossman, J.N., 1989, The computer analysis

of high resolution gamma-ray spectra from instrumental neutron activation analysis experiments: U.S. Geological Survey

Open-File Report 89–454, 98 p.

———1994, The SPECTRA program library; a PC based system

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The chemical analysis of Argonne Premium Coal samples:

U.S. Geological Survey Open-File Report 91–638, chap. F,

p. 50–63.

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33

Determination of Selected Elements in Coal Ash from 

Eight Argonne Premium Coal Samples by 

Atomic Absorption Spectrometry and Atomic Emission Spectrometry

By Michael W. Doughten

ABSTRACT

Methods for the determination of 22 elements in coal

ash from Argonne Premium Coals by inductively coupled

argon plasma-atomic emission spectrometry and flame and

graphite furnace atomic absorption spectrometry are

described. Coal ashes were analyzed in triplicate to determine the precision of the methods. Results of the analyses

of National Institute of Standards and Technology (NIST)

standard reference materials 1633 and 1633a are reported.

Accuracy of the methods was determined by comparing element concentrations in standard reference materials determined in this study with their certified values and literature

values.

INTRODUCTION

Procedures are described and results are presented for

the determination of 22 elements in the coal ashes from 8

Argonne Premium Coal samples by inductively coupled

argon plasma-atomic emission spectrometry (ICAP-AES)

and atomic absorption spectrometry (AAS). Results of the

ICAP-AES and AAS analyses of two standard reference

materials from the National Institute of Standards and Technology (formerly the National Bureau of Standards, NBS),

NIST 1633 and 1633a (coal fly ashes), are included and are

compared with their certified values as well as with other

values reported in the literature. Cadmium and lead were

determined by graphite furnace atomic absorption spectrometry (GFAAS); cobalt and lithium were determined by

flame atomic absorption spectrometry (FAAS). All other

elements were determined by ICAP-AES. All the analyses

described in this paper were performed in the U.S. Geological Survey laboratory in Reston, Va.

SAMPLE PREPARATION

 Raw coal samples were ashed by weighing 70 g of

coal into a previously weighed porcelain crucible. The crucible was placed in an electric furnace, which was slowly

heated to 200 ̊C. After 1.5 hours at 200 ̊C, the temperature

was increased to 350 ̊C and was held at that temperature for

2 hours. The temperature was then increased to 525 ̊C and

maintained for about 36 hours. After the sample cooled for 1

to 2 hours, the weight of the ash was determined by subtracting the weight of the crucible from the weight of the

crucible plus ash. Ash yield was reported as percent ash and

was calculated by:

Percent ash data are listed in table 1. 

Sample solutions for analysis by ICAP-AES and AAS

were prepared by weighing 100 mg of the coal ash and placing it in a 75-mL Teflon screwcap bomb, then adding 7 mL

of concentrated nitric acid. The bomb was capped and

heated on a hotplate overnight at 200 ̊C. After cooling, the

bomb was uncapped, and 2 mL of concentrated nitric acid, 2

mL of concentrated perchloric acid, and 10 mL of hydrofluoric acid were added. All acids used were reagent grade.

The bomb was then recapped and again heated on a hotplate

at 200 ̊C for 4 hours. The bomb was uncapped, and the solution evaporated to dryness. The sample was allowed to cool,

Percent ash ( ) weight ash

( ) weight coal = ------------------------------  ́ 100

Table 1. Coal ash yields for Argonne

Premium Coal samples.

[Coal ash yields determined by Larry Winters, U.S. Geological Survey] 

Coal sample Percent ash

UF PC-1-1 .......................... 13.5

WY PC-2-1......................... 8.5

IL PC-3-1............................ 16.2

PITT PC-4-1....................... 9.2

POC PC-5-1 ....................... 5.3

UT PC-6-1.......................... 4.6

WV PC-7-1......................... 19.4

ND PC-8-1.......................... 9.5
34 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

and 10 mL of 2N hydrochloric acid was added. The bomb

was recapped once again and gently heated until the solution was clear, indicating complete dissolution. The solution

was then transferred to a 15-mL polyethylene tube. This

digestion procedure was used to determine that the concentration of the coal ash in solution was 1 percent. 

SAMPLE ANALYSIS

The determinations of Ba, Be, Cr, Cu, Mn, Ni, Sr, V, Y,

Zn, K, P, and Ti were made directly on this solution by

ICAP-AES using a Jarrell-Ash model 1160 Atomcomp ICP

system. Cobalt and lithium were determined on this solution

by FAAS using a Perkin-Elmer model 5000 atomic absorption spectrometer. A deuterium arc lamp background corrector was used for Co. Lithium requires no background

correction. Concentrations for Co and Li were calculated

from a calibration curve established by analyzing a set of

cobalt and lithium standard solutions. 

The sample solution was diluted 1 to 10 with 2N

hydrochloric acid and analyzed for sodium and magnesium

by ICAP-AES. Cadmium was determined on this solution

by using a Perkin-Elmer atomic absorption spectrometer

with a graphite furnace assembly (model HGA 500) and a

Zeeman background correction system. Lead was determined on this solution by using a Perkin-Elmer model 603

atomic absorption spectrometer with a graphite furnace

assembly (model HGA 2100) and a deuterium arc lamp

background correction system. A 2 percent solution of

ammonium phosphate (NH4H2PO4) (see table 2) was used as

a matrix modifier for both Cd and Pb. Concentrations for Cd

and Pb were calculated from a calibration curve (absorbance

versus concentration (μg/g)) established from analyzing a

set of Cd and Pb standard solutions. This diluted solution

was further diluted to 1 to 100 with 2N hydrochloric acid

and analyzed for aluminum, calcium, and iron by ICAPAES.

All calibration solutions for AAS and AES were prepared in 2N hydrochloric acid. Instrumental operating

parameters for GFAAS and FAAS are listed in tables 2 and

3. ICAP-AES wavelengths and concentration ranges are

listed in table 4. Trace- and major-element concentrations

are listed in tables 5 and 6.

Table 2. GFAAS (graphite furnace atomic absorption spectrometry) operating conditions. 

Cd Pb

Wavelength.......................... 228.8 nm 283.3 nm

Bandpass ............................. 0.7 nm 0.7 nm

Source lamp ........................ Hollow cathode Hollow cathode

Graphite tube....................... Uncoated Uncoated

Sample size ......................... 20 mL 10 mL 

Matrix modifier, 2 percent

 solution of NH4H2PO4..... 10 mL 10 mL 

Drying temperature ............. 110 ̊C 110 ̊C 

Drying time: 

 Ramp.............................. 10 sec 0 sec

 Hold................................ 30 sec 30 sec

Charring temperature .......... 250 ̊C 950 ̊C

Charring time: 

 Ramp.............................. 5 sec 0 sec

 Hold................................ 25 sec 20 sec

Atomizing temperature ....... 2,300 ̊C 2,700 ̊C

Atomizing time:

Ramp............................... 0 sec 0 sec

Hold................................. 5 sec 5 sec

Background correction........ Zeeman Deuterium

Calibration standard concentration range............... 0–4 ng/mL 0–0.2 μg/mL

Lower limit.......................... 0.2 ng/mL 0 .01 μg/mL

Table 3. FAAS (flame atomic absorption spectrometry) operating conditions.

[Flame is fuel lean air-acetylene] 

 Co Li

Wavelength ...................... 240.7 nm 670.8 nm

Bandpass.......................... 0.7 nm 0.4 nm

Source lamp ..................... Hollow cathode Hollow cathode

Background correction .... Deuterium None

Calibration standard concentration range ........... 0–5 μg/mL 0–2 μg/mL

Lower limit ...................... 0.1 μg/mL 0.1 μg/mL

Table 4. ICAP-AES (inductively coupled argon plasma-atomic

emission spectrometry) wavelengths, calibration ranges, and

detection limits. 

1Calibration standard concentration range.

Element Wavelength

(nm)

Calibration

range1

(μg/mL)

Limit of 

detection

(in solution)

(μg/mL)

Al ........................... 308.2 0–2 0.5

Ba........................... 455.4 0–20 .5

Be .......................... 313.0 0–1 .1

Ca........................... 317.9 0–1 .5

Fe ........................... 259.9 0–20 .5

K ............................ 766.5 10–200 10

Mg.......................... 280.2 0–10 .5

Mn.......................... 257.6 0–10 .5

Na........................... 589.0 0–10 .5

Ni ........................... 231.6 0–1 .1

P............................. 214.9 0–50 1

Sr............................ 407.7 0–5 .1

Ti............................ 334.9 0–100 1

V ............................ 292.4 0–1 .1

Zn........................... 213.8 0–1 .1
ATOMIC ABSORPTION SPECTROMETRY AND ATOMIC EMISSION SPECTROMETRY 35

Table 5. Trace-element concentrations (in micrograms per gram, μg/g) in coal ash from eight Argonne Premium Coal samples.

[Cd and Pb were determined by graphite furnace atomic absorption spectrometry, Co and Li were determined by flame atomic absorption spectrometry, and

all other element concentrations were determined by inductively coupled argon plasma-atomic emission spectrometry. —, no data] 

Coal ash Ba Be Cd Co Cr Cu Li Mn Ni Pb Sr V Y Zn

UF PC-1-1 ............... 400 11 0.53 38 150 140 110 300 110 58 440 190 69 140

UF PC-1-2 ............... 410 11 .51 38 140 140 110 310 100 55 450 190 69 140

UF PC-1-3 ............... 420 11 .54 35 150 140 110 300 110 51 430 190 68 150

WY PC-2-1.............. 180 3.1 1.1 19 73 140 48 240 58 37 1,800 160 46 120

WY PC-2-2.............. 180 2.8 1.1 19 75 140 49 250 55 35 1,700 160 44 120

WY PC-2-3.............. 170 2.9 1.1 19 71 150 48 220 61 32 1,800 160 44 120

IL PC-3-1................. 420 4.8 3.7 26 190 65 48 470 110 42 180 200 26 1,000

IL PC-3-2................. 540 4.6 4.0 28 200 64 49 480 120 39 180 200 26 1,100

IL PC-3-3................. 540 4.6 3.5 26 190 64 48 470 110 39 180 190 26 1,200

PITT PC-4-1............ 460 8.3 .64 26 160 60 95 200 99 32 700 160 47 89

PITT PC-4-2............ 450 8.3 .63 28 150 58 93 190 90 32 700 160 46 81

PITT PC-4-3............ 430 8.5 .68 26 140 60 94 190 88 32 680 160 46 84

POC PC-5-1............. 310 15 1.6 71 180 220 110 300 130 48 1,600 200 120 73

POC PC-5-2............. 310 15 1.4 71 160 220 110 300 120 45 1,600 200 130 77

POC PC-5-3............. 310 15 1.4 71 180 220 110 300 130 45 1,600 200 110 74

UT PC-6-1............... 690 2.8 1.3 18 110 84 110 88 73 34 1,300 86 45 140

UT PC-6-2............... 660 2.7 1.3 18 99 82 110 88 71 34 1,300 87 46 130

WV PC-7-1.............. 610 9.7 .40 40 210 100 150 80 81 63 250 220 55 65

WV PC-7-2.............. 630 9.8 .37 43 210 100 150 78 82 61 240 230 54 66

WV PC-7-3.............. 680 10. .44 42 200 100 150 77 82 63 260 220 57 63

ND PC-8-1............... 4,500 1.9 .50 <10 27 59 28 840 15 16 5,400 37 20 54

ND PC-8-2............... 4,100 1.8 .46 <10 26 37 28 830 15 16 5,300 36 19 49

ND PC-8-3............... 4,700 — .48 <10 24 52 30 850 12 16 5,300 38 — 47

Table 6. Major-element concentrations (in weight percent) in coal ash from eight Argonne

Premium Coal samples.

[Element concentrations were determined by inductively coupled argon plasma-atomic emission spectrometry]

Coal ash Al Ca Fe K Mg Na P Ti

UF PC-1-1 ............... 11.9 3.31 13.8 2.10 0.61 0.24 0.056 0.58

UF PC-1-2 ............... 11.9 3.30 14.0 2.10 .61 .24 .059 .59

UF PC-1-3 ............... 11.8 3.28 13.6 2.10 .61 .24 .061 .58

WY PC-2-1.............. 8.18 14.2 4.21 .33 2.83 1.40 .31 .66

WY PC-2-2.............. 8.21 13.6 4.46 .33 2.78 1.37 .29 .66

WY PC-2-3.............. 8.26 14.3 4.28 .31 2.81 1.40 .30 .65

IL PC-3-1................. 7.75 5.82 16.8 1.20 .47 .60 .036 .43

IL PC-3-2................. 7.70 5.96 16.4 1.20 .48 .61 .037 .43

IL PC-3-3................. 7.72 6.00 17.2 1.20 .47 .58 .037 .42

PITT PC-4-1............ 10.8 2.29 14.6 1.20 .41 .35 .12 .62

PITT PC-4-2............ 10.9 2.23 14.3 1.20 .41 .35 .12 .61

PITT PC-4-3............ 10.8 2.21 14.2 1.20 .40 .34 .12 .60

POC PC-5-1............. 10.4 8.75 9.67 .51 1.06 1.57 .042 .72

POC PC-5-2............. 10.4 8.53 9.52 .53 1.04 1.57 .041 .72

POC PC-5-3............. 10.3 8.53 9.50 .53 1.04 1.54 .040 .72

UT PC-6-1............... 7.56 9.07 6.16 .30 .64 2.75 .020 .50

UT PC-6-2............... 7.50 8.70 6.09 .30 .65 2.70 .021 .49

WV PC-7-1.............. 16.1 .29 2.04 2.52 .48 .17 .046 1.34

WV PC-7-2.............. 16.4 .30 1.96 2.58 .49 .18 .045 1.34

WV PC-7-3.............. 16.3 .30 1.95 2.55 .49 .18 .038 1.34

ND PC-8-1............... 4.17 16.0 4.91 .13 4.16 4.84 .13 .21

ND PC-8-2............... 4.22 16.1 4.95 .16 4.16 4.89 .13 .20

ND PC-8-3............... 4.25 16.5 5.05 .15 4.26 5.00 .13 .21
36 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 7. Comparison of element concentrations in NIST standard reference material 1633 determined in this study with certified values

and with concentrations determined in other studies.

[Concentrations for the first 14 elements are in micrograms per gram (μg/g); others are in weight percent. Methods used in this study: ICAP-AES, inductively coupled argon plasma-atomic emission spectrometry; GFAAS, graphite furnace atomic absorption spectrometry; FAAS, flame atomic absorption

spectrometry. NIST, National Institute of Standards and Technology, formerly the National Bureau of Standards (NBS). Certified and information values for

NIST 1633 are from NBS (1975). —, no data] 

1Values with no error listed are NIST information values; all others are NIST certified values.

Element

This study NBS 

(1975)1

Gladney and others 

(1987)

Kane 

(1989)

Ondov and others 

(1975)

Rowe and Steinnes 

(1977) Method Conc.

Ba (μg/g).. ICAP-AES 2,700 — 2,665 ± 160 — 2,700 ± 200 2,540

Be ............. ICAP-AES 11 — 12.1 ± 1.0 — — —

Cd............. GFAAS 1.5 1.45 ± 0.06 1.47 ± 0.15 1.56 ± 0.26 — —

Co ............ FAAS 41 38 40 ± 3 — 41.5 ± 1.2 40.3 ± 0.4

Cr.............. ICAP-AES 130 131 ± 2 127 ± 10 — 127 ± 6 129.2 ± 2.7

Cu............. ICAP-AES 130 128 ± 5 129 ± 7 130 ± 6 — 115 ± 8

Li.............. FAAS 160 — 170 ± 80 170 ± 13 — —

Mn............ ICAP-AES 510 493 ± 7 494 ± 20 496 ± 34 496 ± 19 488 ± 14

Ni.............. ICAP-AES 94 98 ± 7 98 ± 6 — 98 ± 9 69 ± 7

Pb ............. GFAAS 70 70 ± 4 72 ± 6 67 ± 4 75 ± 5 —

Sr.............. ICAP-AES 1,400 1,430 ± 60 1,380 ± 100 — 1,700 ± 300 1,430 ± 60

V............... ICAP-AES 220 214 ± 8 224 ± 24 — 235 ± 13 237 ± 20

Y............... ICAP-AES 66 — 64 ± 4 — 62 ± 10 —

Zn ............. ICAP-AES 210 210 ± 20 211 ± 11 210 ± 10 216 ± 25 201 ± 6

Al (%)....... ICAP-AES 11.9 — 12.6 ± 0.6 — 12.7 ± 0.5 12.35 ± 0.25

Ca ............. ICAP-AES 4.58 — 4.65 ± 0.34 — 4.7 ± 0.6 4.69 ± 0.14

Fe ............. ICAP-AES 6.05 — 6.16 ± 0.27 — 6.2 ± 0.3 6.2 ± 0.05

K............... ICAP-AES 1.80 1.72 1.69 ± 0.09 — 1.61 ± 0.15 1.80 ± 0.13

Mg............ ICAP-AES 1.33 1.98 1.5 ± 0.3 1.17 ± 0.049 1.8 ± 0.4 1.78 ± 0.2

Na............. ICAP-AES .31 .307 .313 ± 0.02 .295 ± 0.023 .32 ± 0.04 .283 ± 0.014

P ............... ICAP-AES .12 — .101 ± 0.018 — — —

Ti .............. ICAP-AES .77 — .71 ± 0.05 — .74 ± 0.03 .70 ± 0.03

DISCUSSION

NIST standard reference materials 1633 and 1633a

were used as control standards for each determination. Each

Argonne Premium Coal sample was run in triplicate

(labeled 1, 2, and 3) with the exception of UT PC-6, which

was run in duplicate due to a lack of available sample. Data

for these analyses are shown in tables 5 and 6. The replicate

analyses show the precision of the methods used. The relative percent standard deviation was generally about ±5 percent. Comparison of the analyses of these control standards

with NIST certified values (NBS, 1975, 1979), with AAS

values (Kane, 1989), and with values determined by instrumental neutron activation analysis (Ondov and others, 1975;

Rowe and Steinnes, 1977) shows the accuracy of the methods (tables 7 and 8). 

ICAP-AES in Reston of samples WY PC-2 and POC

PC-5 determined lower concentrations of barium and strontium than other methods of analysis (see table 2 in paper by

Palmer and Klizas, this volume). They were probably

caused by incomplete dissolution of barium sulfate present

in the sample. Low Sr results may have been caused by Sr

co-precipitating with Ba. 

Sample IL PC-3 showed a wide concentration range

for Ba (420–540 μg/g). Sample ND PC-8 showed low concentrations of potassium. These values were close to the

detection limit, and that may account for the error. This also

could be due to sampling error or incomplete digestion of

barite that may be present in the sample. 

Beryllium values determined by ICAP-AES were corrected for vanadium and titanium interferences, and zinc

values determined by ICAP-AES were corrected for interferences by manganese, iron, and vanadium. Interference

corrections vary depending on the instrument operating conditions used and should be determined before the start of the

analysis.
ATOMIC ABSORPTION SPECTROMETRY AND ATOMIC EMISSION SPECTROMETRY 37

REFERENCES

Gladney, E.S., O'Malley, B.T., Roelandts, J., and Gills, T.E., 1987,

Compilation of elemental concentration data for NBS clinical, biological, geological, and environmental standard reference materials: National Bureau of Standards Special Publication 260–111, p. 1633-1–1633-26, 1633a-1–1633a-14.

Kane, J.S., 1989, The determination of selected elements in coal

ash by atomic absorption spectrometry in Golightly, D.W.,

and Simon, F.O., eds., Methods for sampling and inorganic

analysis of coal: U.S. Geological Survey Bulletin 1823, p.

47–53.

National Bureau of Standards, 1975, National Bureau of Standards

certificate of analysis, standard reference material 1633, trace

elements in coal fly ash: Washington, D.C., National Bureau

of Standards, 2 p.

———1979, National Bureau of Standards certificate of analysis,

standard reference material 1633a, trace elements in coal fly

ash: Washington, D.C., National Bureau of Standards, 2 p.

Ondov, J.M., Zoller, W.H., Olmez, Ilham, Aras, N.K., Gordon,

G.E., Rancitelli, L.A., Abel, K.H., Filby, R.H., Shah, K.R.,

and Ragaini, R.C., 1975, Elemental concentrations in the

National Bureau of Standards’ environmental coal and fly ash

standard reference materials: Analytical Chemistry, v. 47, no.

7, p. 1102–1109.

Rowe, J.J., and Steinnes, E., 1977, Instrumental activation analysis

of coal and fly ash with thermal and epithermal neutrons:

Journal of Radioanalytical Chemistry, v. 37, no. 2, p. 849–

856.

Table 8. Comparison of element concentrations in NIST standard reference material 1633a determined

in this study with certified values and with concentrations determined in other studies.

[Concentrations for the first 14 elements are in micrograms per gram (μg/g); others are in weight percent. Methods used

in this study: ICAP-AES, inductively coupled argon plasma-atomic emission spectrometry; GFAAS, graphite furnace

atomic absorption spectrometry; FAAS, flame atomic absorption spectrometry. NIST, National Institute of Standards

and Technology, formerly the National Bureau of Standards (NBS). Certified and information values for NIST 1633a are

from NBS (1979). —, no data] 

1 Values with no error listed are NIST information values; all others are NIST certified values.

Element

This study

NBS (1979)1 Gladney and others (1987) Kane (1989)

Method Conc.

Ba (μg/g)... ICAP-AES 1,400 1,500 1,420 ± 100 —

Be .............. ICAP-AES 12 12 12.8 ± 0.6 —

Cd.............. GFAAS .94 1.0 ± 0.15 1.12 ± 0.17 0.98 ± 0.08

Co ............. FAAS 46 46 43 ± 3 —

Cr............... ICAP-AES 190 196 ± 6 194 ± 7 —

Cu.............. ICAP-AES 110 118 ± 3 120 ± 4 114 ± 7

Li............... FAAS 170 — 165 ± 50 184 ± 14

Mn............. ICAP-AES 180 179 ± 8 188 ± 15 160 ± 12

Ni............... ICAP-AES 130 127 ± 4 124 ± 13 —

Pb .............. GFAAS 71 72.4 ± 0.4 72 ± 4 62 ± 4

Sr............... ICAP-AES 850 830 ± 30 810 ± 40 —

V................ ICAP-AES 290 297 ± 6 294 ± 18 —

Y................ ICAP-AES 87 — 82 ± 6 —

Zn .............. ICAP-AES 210 220 ± 10 226 ± 22 211 ± 11

Al (%)........ ICAP-AES 14.0 14.3 ± 1.0 14.4 ± 0.6 —

Ca .............. ICAP-AES 1.14 1.11 ± 0.01 1.14 ± 0.06 —

Fe .............. ICAP-AES 9.18 9.40 ± 0.1 9.37 ± 0.23 —

K................ ICAP-AES 1.95 1.88 ± 0.06 1.88 ± 0.05 —

Mg............. ICAP-AES .44 .455 ± 0.01 .457 ± 0.045 .436 ± 0.005

Na.............. ICAP-AES .17 .17 ± 0.01 .173 ± 0.011 .158 ± 0.014

P ................ ICAP-AES .18 — .169 ± 0.024 —

Ti ............... ICAP-AES .92 0.8 .823 ± 0.034 —
39

Determination of 25 Elements in Coal Ash from 

8 Argonne Premium Coal Samples by 

Inductively Coupled Argon Plasma-Atomic Emission Spectrometry

By Paul H. Briggs

ABSTRACT

Twenty-five major and trace elements were determined

in coal ash material by inductively coupled argon plasmaatomic emission spectrometry (ICAP-AES). Two decomposition techniques were used. Coal ashes were analyzed in

triplicate to determine the precision of the method. The

National Institute of Standards and Technology (NIST), formerly the National Bureau of Standards (NBS), standard

reference material 1632a and U.S. Geological Survey

(USGS) standard reference material CLB-1 were used to

assess the accuracy of the method. 

INTRODUCTION

Inductively coupled argon plasma-atomic emission

spectrometry (ICAP-AES) is rapidly becoming a common

method to determine many major and trace elements in geologic materials. An overview of ICAP-AES analysis was

given by Lichte and others (1987). Recently, the ICAP-AES

method was expanded to include the analysis of coal by

using an acid dissolution procedure (Doughten and Gillison,

1990). This work included new methods combining results

from two different decomposition procedures that were used

to determine the concentrations of 25 elements in coal ashes

from 8 Argonne Premium Coal samples by ICAP-AES.

Fourteen elements were determined by an acid decomposition using a mixture of hydrochloric, nitric, perchloric, and

hydrofluoric acids at a low temperature in a method

described by Crock and others (1983). Eleven additional

elements were determined by a sodium peroxide sinter

decomposition technique modified from one described by

Borsier and Garcia (1983). The digested sample was aspirated into the ICAP discharge where the elemental emission

signal was measured simultaneously for the elements of

interest.

EXPERIMENTAL

All ICAP-AES measurements described in this paper

were performed on a Thermo Jarrell-Ash model 1160

Plasma Atomcomp simultaneous instrument in the U.S.

Geological Survey (USGS) laboratory in Denver, Colo.

ICAP-AES calibration was performed using USGS reference material BHVO-1, Canadian Certified Reference

Materials Project SY-3, and four multielement solutions.

The wavelengths, operating ranges, and decomposition

methods are given in table 1. The ICAP-AES operating conditions are given in table 2.

Two decomposition procedures were used to determine

the 25 elements. The acid decomposition technique was

used for the determination of the trace elements Be, Co, Cr,

Cu, Li, Mn, Ni, Sc, Sr, Th, V, Y, and Zn and the major element Na. The trace-element suite was chosen in order to

give the best reporting limits for the 100-fold dilution and

the ease of solubility by the acid decomposition. Sodium is

reported with the trace suite because sodium peroxide was

the sintering flux used for the sample decomposition for

major-element determinations.

Coal ash sample solutions from the acid decomposition

were prepared in the following manner: a 0.200-g sample, to

which a solution containing 100 μg lutetium had been added

as an internal standard, was digested and evaporated to dryness in a 30-mL Teflon vessel with 3 mL HCl, 2 mL HNO3,

1 mL HClO4, and 2 mL HF at 110 ̊C. An additional 1 mL

HClO4 was added to the residue and taken to dryness again

at 160 ̊C. One milliliter HNO3 and one drop 30 percent H2O2

were added to the residue, and 20 mL of 1 percent HNO3

was added to the solution. The solution was transferred to a

13¥100-mm polypropylene test tube and capped until ready

for ICAP-AES analysis. All reagents used in the procedures

were reagent grade or better. It should be noted that this

solution was used for both ICAP-AES and inductively coupled argon plasma-mass spectrometry (ICAP-MS) to minimize duplication of digestion and maximize the efforts of

the laboratory staff. (See ICAP-MS analysis in Meier’s

paper in this volume.)
40 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

The 11 elements reported from the Na2O2 sinter

decomposition are the major elements Al, Ca, Fe, K, Mg, P,

Si, and Ti, and the trace elements B, Ba, and Zr. The Na2O2

sinter technique was used to decompose resistant mineral

phases like barite and zircon (for the elements Ba and Zr)

and to make soluble boron and silicon, which are volatilized

in the acid decomposition. The large dilution factor (1:400)

does not degrade the reportability for the major elements

because of their high concentrations in the ashed coals. 

Coal ash sample solutions from the sinter decomposition were prepared in the following manner: a 0.100-g sample and 0.5 g of finely ground Na2O2 were mixed in a 5-mL

graphite crucible with a Teflon stirring rod and sintered for

35 minutes at 445 ̊C. The crucible was allowed to cool to

Table 2. Operating conditions for ICAP-AES (inductively

coupled argon plasma-atomic emission spectrometry). 

Forward power .....................................1,250 W

Sample argon flow rate.........................0.5 L/min

Coolant argon flow rate ........................18 L/min

Sample pump rate.................................0.7 mL/min

Observation height ...............................14.5 mm above load coil

Nebulizer ..............................................Modified Babington

Table 1. Wavelengths, operating ranges, and decomposition

methods used for determining concentrations of 25 elements in

coal ash from 8 Argonne Premium Coal samples by ICAP-AES

(inductively coupled argon plasma-atomic emission spectrometry).

[l, wavelength; nm, nanometer; ppm, parts per million; %, weight percent]

Element l (nm) Range Decomposition

Al................. 309.2 0.04–100 % Sinter

B.................. 249.7 40–10,000 ppm Sinter

Ba ................ 455.4 8–10,000 ppm Sinter

Be ................ 313.0 4–10,000 ppm Acid

Ca ................ 317.9 0.04–100 % Sinter

Co................ 228.6 4–10,000 ppm Acid

Cr................. 267.7 4–10,000 ppm Acid

Cu................ 324.7 4–10,000 ppm Acid

Fe................. 271.4 0.04–100 % Sinter

K.................. 766.4 0.04–100 % Sinter

Li................. 670.7 8–10,000 ppm Acid

Mg............... 285.2 0.04–100 % Sinter

Mn............... 257.6 16–10,000 ppm Acid

Na................ 588.9 0.01–100 % Acid

Ni................. 231.6 8–10,000 ppm Acid

P .................. 213.6 0.04–100 % Sinter

Sc................. 424.6 8–10,000 ppm Acid

Si ................. 251.6 0.04–100 % Sinter

Sr................. 421.5 8–10,000 ppm Acid

Th ................ 401.9 16–10,000 ppm Acid

Ti ................. 334.9 0.04–100 % Sinter

V.................. 292.4 8–10,000 ppm Acid

Y.................. 321.6 8–10,000 ppm Acid

Zn ................ 213.8 8–10,000 ppm Acid

Zr................. 339.1 16–10,000 ppm Sinter

room temperature and was placed in a 50-mL Teflon beaker.

Twenty milliliters of deionized H2O, 20 mL of 20 percent

HNO3, and 200 μg of lutetium in solution (an internal standard) were added in that order. The solution was transferred

to a 13¥100-mm test tube and analyzed by ICAP-AES. As

discussed earlier, this solution was used for both ICAP-AES

and ICAP-MS. (See ICAP-MS analysis in Meier’s paper in

this volume.)

RESULTS AND DISCUSSION

Table 3 gives the results of triplicate analyses of the

eight ashed coal samples digested by the acid decomposition method. Table 4 presents the results of triplicate analyses of the eight ashed coal samples digested by the sinter

decomposition technique. Generally, the precision for both

decomposition techniques is within ±5–10 percent relative

standard deviation (RSD). 

The copper content of sample ND PC-8-3 is dissimilar

to the contents of the other replicates and is attributed to a

contaminated acid digestion. A high value occurs for zinc in

sample PITT PC-4-1. Again, the probable explanation is

contamination from the acid digestion. Boron and barium

have erroneous values for samples UF PC-1-3 and show

large disagreement for all splits of WV PC-7. Low values of

MgO, CaO, and TiO2 for sample IL PC-3-3 are attributed to

the sinter preparation rather than ICAP-AES analysis. 

Confirmation of accuracy was evaluated by data for

NIST standard reference material 1632a and USGS standard reference material CLB-1 that have undergone the two

decomposition techniques. Tables 5 and 6 compare data for

this study from two ashed coal standards with values from

other studies (Gladney and others, 1984; J.S. Kane, unpub.

data, 1990). The data from this study show good agreement

with results from other studies.
INDUCTIVELY COUPLED ARGON PLASMA-ATOMIC EMISSION SPECTROMETRY 41

Table 3. Concentrations of Na2O (in weight percent) and trace elements (in parts per million) in eight Argonne Premium Coal samples

ashed and then digested by acid decomposition.

[Three analyses were done for each sample by ICAP-AES (inductively coupled argon plasma-atomic emission spectrometry)] 

Coal ash Na2O Be Co Cr Cu Li Mn Ni Sc Sr Th V Y Zn

UF PC-1-1 ........ 0.34 11 39 160 140 110 330 110 29 430 21 200 63 140

UF PC-1-2 ........ .34 11 39 160 140 110 330 110 29 430 21 200 60 140

UF PC-1-3 ........ .35 11 40 160 130 110 320 110 29 430 19 200 56 140

WY PC-2-1....... 1.9 3 18 74 150 46 240 55 19 3,000 16 170 42 150

WY PC-2-2....... 1.9 3 21 76 160 46 240 57 19 3,000 19 170 42 130

WY PC-2-3....... 1.9 3 20 75 160 46 220 55 20 3,100 15 170 43 140

IL PC-3-1.......... .88 4 29 300 67 46 570 180 17 190 15 240 26 1,100

IL PC-3-2.......... .93 4 27 210 69 47 520 120 17 200 13 230 26 1,300

IL PC-3-3.......... .86 4 26 210 64 46 520 120 16 190 12 220 23 1,200

PITT PC-4-1..... .50 8 28 170 59 89 230 97 27 690 19 178 43 150

PITT PC-4-2..... .50 8 29 170 68 90 230 100 27 700 15 180 42 88

PITT PC-4-3..... .49 8 28 170 62 89 220 100 27 680 17 180 43 88

POC PC-5-1...... 2.1 15 75 190 310 100 340 140 33 2,100 23 230 110 100

POC PC-5-2...... 2.1 15 73 180 310 100 340 139 34 2,000 20 230 110 100

POC PC-5-3...... 2.1 15 75 180 310 110 350 140 33 2,100 22 230 110 100

UT PC-6-1........ 3.9 3 21 150 94 120 93 79 17 1,300 13 100 45 100

UT PC-6-2........ 3.8 3 20 110 92 120 92 74 16 1,300 13 96 43 110

UT PC-6-3........ 3.8 3 20 110 89 120 89 75 16 1,300 12 95 43 100

WV PC-7-1....... .24 11 38 200 110 140 71 81 38 320 32 220 63 55

WV PC-7-2....... .24 11 39 200 110 144 70 84 38 320 33 220 67 54

WV PC-7-3....... .24 11 38 200 110 140 72 81 38 320 34 220 62 58

ND PC-8-1........ 7.0 2 8 23 48 28 850 14 8 5,200 6 41 23 54

ND PC-8-2........ 7.0 2 10 23 51 28 870 16 8 5,200 8 40 24 49

ND PC-8-3........ 7.0 2 9 26 130 28 870 15 8 5,200 7 41 23 50
42 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 4. Concentrations of major oxides (in weight percent) and trace elements (in parts per million) in eight

Argonne Premium Coal samples ashed and then digested by sinter decomposition.

[Three analyses were done for each sample by ICAP-AES (inductively coupled argon plasma-atomic emission spectrometry)] 

Coal ash Al2O3 CaO Fe2O3 K2O MgO P2O5 SiO2 TiO2 B Ba Zr

UF PC-1-1........... 21 4.1 17 2.5 0.92 0.10 40 0.89 260 390 180

UF PC-1-2........... 22 4.2 18 2.7 1.0 .10 41 .92 230 380 180

UF PC-1-3........... 23 4.2 18 2.6 .98 .10 42 .96 360 470 190

WY PC-2-1 ......... 14 17 5.2 .38 3.8 .57 25 .95 1,000 3,300 210

WY PC-2-2 ......... 14 16 5.9 .50 3.8 .56 26 .97 1,300 3,400 220

WY PC-2-3 ......... 16 19 5.8 .54 4.4 .67 28 1.1 1,100 3,600 230

IL PC-3-1 ............ 16 8.3 21 1.7 .80 .06 41 .74 1,000 510 170

IL PC-3-2 ............ 15 8.1 22 1.6 .77 .05 40 .73 1,000 480 140

IL PC-3-3 ............ 14 7.5 20 1.6 .70 .04 36 .66 970 530 120

PITT PC-4-1........ 20 2.8 19 1.5 .60 .23 42 .93 520 420 200

PITT PC-4-2........ 20 2.8 19 1.5 .60 .22 42 .92 530 420 200

PITT PC-4-3........ 19 2.9 19 1.5 .59 .22 41 .89 510 410 190

POC PC-5-1 ........ 21 12 14 .83 1.8 .10 31 1.3 260 4,100 320

POC PC-5-2 ........ 20 12 13 .82 1.7 .10 30 1.2 240 3,800 300

POC PC-5-3 ........ 20 12 13 .72 1.7 .09 29 1.2 240 3,800 290

UT PC-6-............. 15 12 9.0 .70 1.0 .04 41 .85 2,700 710 360

UT PC-6-2........... 16 13 9.1 .73 1.1 .04 43 .85 2,700 730 390

UT PC-6-3........... 16 13 9.6 .76 1.1 .03 44 .89 2,900 800 370

WV PC-7-1 ......... 30 .40 3.0 2.9 .70 .09 53 1.9 200 570 340

WV PC-7-2 ......... 33 .44 2.9 3.3 .77 .09 59 2.1 400 740 380

WV PC-7-3 ......... 31 .42 2.8 3.0 .72 .09 55 2.0 360 620 350

ND PC-8-1 .......... 7.9 21 6.7 .56 6.1 .30 15 .32 830 5,500 120

ND PC-8-2 .......... 7.9 21 7.0 .41 6.2 .30 15 .32 850 5,600 140

ND PC-8-3 .......... 7.8 21 6.9 .45 6.1 .29 15 .31 830 5,600 120
INDUCTIVELY COUPLED ARGON PLASMA-ATOMIC EMISSION SPECTROMETRY 43

REFERENCES

Borsier, M., and Garcia, M., 1983, Analyse automatique d'echantillons geologiques par plasma ICP: Spectrochimica Acta, v.

38B, nos. 1/2, p. 123–127.

Crock, J.G., Lichte, F.E., and Briggs, P.H., 1983, Determination of

elements in National Bureau of Standards’ geological reference materials SRM 278 obsidian and SRM 688 basalt by

inductively coupled argon plasma-atomic emission spectrometry: Geostandards Newsletter, v. 7, no. 2, p. 335–340.

Doughten, M.W., and Gillison, J.R., 1990, Determination of

selected elements in whole coal and in coal ash from the eight

Argonne Premium Coal samples by atomic absorption spectrometry, atomic emission spectrometry and ion selective

electrode: Energy and Fuels, v. 4, no. 5, p. 426–430.

Gladney, E.S., Burns, C.E., Perrin, D.R., Roelandts, I., and Gills,

T.E., 1984, 1982 compilation of elemental concentration data

for NIST biological, geological, and environmental standard

reference materials: National Bureau of Standards Special

Publication 260–88, p. 21.

Lichte, F.E., Golightly, D.W., and Lamothe, P.J., 1987, Inductively

coupled plasma-atomic emission spectrometry, in Baedecker,

P.A., ed., Methods for geochemical analysis: U.S. Geological

Survey Bulletin 1770, p. B1–B10.

Table 5. Concentrations of Na2O (in weight percent) and trace

elements (in parts per million) in two coal reference materials

ashed and then digested by acid decomposition.

[USGS, U.S. Geological Survey; ICAP-AES, inductively coupled argon

plasma-atomic emission spectrometry; NIST, National Institute of Standards and Technology, formerly the National Bureau of Standards] 

1Reported on a whole-coal basis and converted to an ash basis for comparison.

2Compilation of data obtained by various methods.

USGS CLB-1 NIST 1632a

This study, 

ICAP-AES

J.S. Kane 

(USGS, unpub. 

data, 1990)1,2

This study, 

ICAP-AES

Gladney and 

others 

(1984)1,2

Na2O (%) .... 0.28 0.31 0.48 0.48

Be (ppm)..... 14 16 5 6

Co (ppm) .... 91 87 29 27

Cr (ppm) ..... 130 130 150 150

Cu (ppm) .... 140 140 68 70

Li (ppm)...... 85 110 130 150

Mn (ppm).... 110 120 120 130

Ni (ppm) ..... 250 250 79 85

Sc (ppm) ..... 27 25 27 27

Sr (ppm)...... 880 930 370 380

Th (ppm)..... 20 18 20 19

V (ppm) ...... 160 160 180 190

Y (ppm) ...... 64 58 34 34

Zn (ppm)..... 660 660 120 120

% ash .......... 7.8 23.5

Table 6. Concentrations of major oxides (in weight percent) and

trace elements (in parts per million) in two coal reference materials

ashed and then digested by sinter decomposition.

[USGS, U.S. Geological Survey; ICAP-AES, inductively coupled argon

plasma-atomic emission spectrometry; NIST, National Institute of Standards and Technology, formerly the National Bureau of Standards] 

1Reported on a whole-coal basis and converted to an ash basis for comparison.

2Compilation of data obtained by various methods.

USGS CLB-1 NIST 1632a

This study, 

ICAP-AES

J.S. Kane 

(USGS, unpub. 

data, 1990)1,2

This study, 

ICAP-AES

Gladney and 

others 

(1984)1,2

Al2O3(%)..... 18 19 23 24

CaO (%)...... 2.6 2.9 1.4 1.4

Fe2O3(%)..... 14 16 6.6 6.8

K2O (%) ...... .87 .96 2.1 2.1

MgO (%)..... .53 .62 .70 .85

P2O5 (%)...... .89 .95 .22 .25

SiO2 (%)...... 30 33 53 55

TiO2 (%)...... .91 .98 1.1 1.2

B (ppm)....... 82 46 220 230

Ba (ppm)..... 430 470 440 530

Zr (ppm)...... 170 160 230 230

% ash........... 7.8 23.5
45

Determination of 33 Elements in Coal Ash from

8 Argonne Premium Coal Samples by 

Inductively Coupled Argon Plasma-Mass Spectrometry

By Allen L. Meier

ABSTRACT

Thirty-three elements were determined in the ash of

eight Argonne Premium Coal samples by inductively coupled argon plasma-mass spectrometry (ICAP-MS). Two

sample digestion procedures were used, a sodium peroxide

sinter to dissolve resistant minerals and an acid digestion

technique for acid-soluble minerals in the coal ash. Hf, Ta,

W, and the rare earth elements La, Ce, Pr, Nd, Sm, Eu, Gd,

Tb, Dy, Ho, Er, Tm, and Yb were determined by ICAP-MS

in the solution from the sodium peroxide sinter. Ga, Ge, As,

Rb, Nb, Mo, Ag, Cd, Sn, Sb, Te, Cs, Au, Tl, Pb, Bi, and U

were determined by ICAP-MS in the acid solution. These

solutions were also used for inductively coupled argon

plasma-atomic emission spectrometry (ICAP-AES) determination of other elements to give nearly total elemental

coverage except for the volatile elements, halogens, and elements not retained because of combustion in the ashing process. The technique to determine the value for each element

was selected to provide the best possible precision and

determination limit while minimizing interferences. 

INTRODUCTION

Inductively coupled argon plasma-mass spectrometry

(ICAP-MS) is one of the newest instrumental analytical

techniques to be used for elemental determination in geologic materials. The U.S. Geological Survey (USGS) began

use of the technique in 1985 and developed methods using

ICAP-MS for the determination of rare earth elements

(REE’s) and platinum-group elements and for the analysis

of coal. ICAP-MS is attractive for these applications

because it has multielement measurement capabilities with

very low detection limits. Most elements are detected

directly in solutions in the range of 1 to 100 pg/mL. These

detection limits are often 100 to 1,000 times lower than

those routinely achieved by inductively coupled argon

plasma-atomic emission spectrometry (ICAP-AES). The

response is linear with concentration over about 6 to 8

orders of magnitude, making calibration quite uncomplicated. Another advantage of ICAP-MS is that the mass

spectra of elements are relatively simple. Problems with the

techniques arise from spectral interferences from molecular

species and effects from the sample matrix. These problems

are minimized by the use of corrections for spectral overlaps

and internal standards for matrix effects. For the analysis of

coal, ICAP-MS and ICAP-AES are used as complementary

techniques. ICAP-AES is used to determine the elements

that normally have higher concentrations in the coal ash.

These are primarily the lower mass elements where the

ICAP-MS technique has more interferences. The ICAPAES technique is also used for other elements that are normally found in coal ash above the detection limits for the

technique and where the precision by this technique is better

than the precision of the ICAP-MS technique. ICAP-MS is

used to determine the elements where a lower limit of detection is necessary to determine normal concentrations found

in coal and for elements where the ICAP-AES technique

suffers from interferences. 

EXPERIMENTAL

SINTER METHOD

Hf, Ta, W, and the rare earth elements La, Ce, Pr, Nd,

Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb are made soluble in

a 0.1-g coal ash sample by sintering with sodium peroxide,

leaching with water, and acidifying with nitric acid in a

preparation technique modified from one described by

Borsier and Garcia (1983). Details of the procedure are

described by Briggs in this volume. The elements were then

determined by ICAP-MS at lower reporting limits, in parts

per million, of 2.0 La, 3.0 Ce, 0.5 Pr, 2.0 Nd, 0.5 Sm, 0.2

Eu, 1.0 Gd, 0.5 Tb, 0.2 Dy, 0.5 Ho, 0.2 Er, 0.5 Tm, 0.5 Yb,

1.0 Hf, 1.0 Ta, and 1.0 W. Lutetium was added as an internal

standard to correct for instrument instability and oxide

interferences. Two-point calibration for each element was

made by using the average intensity of five blanks taken
46 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

through the entire procedure, and the intensities were

acquired on a solution of a glass reference standard containing a known concentration of each element. The standard

solution was run at 15 sample intervals, drift was calculated,

and correction was applied between standards. All new

determinations reported in this paper result from work done

in the USGS laboratory in Denver, Colo.

INTERFERENCES FOR THE SINTER METHOD

Isobaric interferences of some metal oxide ions are

quite high for selected REE’s. Therefore, conditions that

minimize the oxide ions were used. The delivery line from

the nebulizer spray chamber to the plasma torch was cooled

to 10°C to reduce the amount of water vapor (the main

source of oxygen) that enters the plasma. Compromise conditions of power and the sheath gas flow rate were selected

to achieve a balance between sensitivity and oxide. A

method modified from Lichte and others (1987) was used to

minimize and correct for these oxide isobaric overlaps.

Oxide interference was subtracted by using the ratio of

oxide ions to element ions in single-element standards and

the oxide/ion ratio of the internal standard. In a 3-hour

period of running samples, the oxide ratios can drift by as

much as 100 percent. This is probably due to a gradual closing of the sampler cone, although several factors are

involved. The oxide correction of PrO on gadolinium-157

must be very accurate. Even after the oxide abundance is

minimized, a 10 percent error in the oxide ratio correction

can result in a 20 percent error in the gadolinium result. The

metal oxide/metal ion ratios of the REE’s all responded similarly to plasma conditions (Lichte and others, 1987). Lutetium, used as an internal standard, was also used to track the

drift in the oxide/metal ratio through a sample run. The

oxide ratios of overlapping elements were measured in standard solutions and compared to the LuO+/Lu+ response.

These ratios were used to mathematically subtract the oxide

interference and to correct for changes in the other metal

oxide ratios due to matrix or drift in the sample run.

ACID DIGESTION METHOD

Ga, Ge, As, Rb, Nb, Mo, Ag, Cd, Sn, Sb, Te, Cs, Au,

Tl, Pb, Bi, and U were made soluble in a 0.2-g coal ash sample by heating with a mixture of hydrochloric, nitric, perchloric, and hydrofluoric acids (Crock and others, 1983).

Details of the procedure are described by Briggs in this volume. The elements were then determined by ICAP-MS at

lower reporting limits, in parts per million, of 0.1 Ga, 0.5

Ge, 1.0 As, 0.5 Rb, 2.0 Nb, 0.5 Mo, 0.5 Ag, 0.2 Cd, 1.0 Sn,

0.5 Sb, 0.5 Te, 0.1 Cs, 0.1 Au, 0.5 Tl, 2.0 Pb, 0.1 Bi, and 0.2

U. Lutetium and indium were added as internal standards to

correct for instrument instability and oxide interferences.

Two-point calibration for each element was made by using

the average intensity of five blanks taken through the entire

procedure, and the intensities were acquired on a solution of

a glass reference standard containing a known concentration

of each element. The standard solution was run at 15 sample

intervals, drift was calculated, and correction was applied

between standards. Oxide interference was subtracted by

using the ratio of oxide ions to element ions in singleelement standards and the oxide/ion ratio of the internal

standard. 

INTERFERENCES FOR THE 

ACID DIGESTION METHOD

Interferences in ICAP-MS come from matrix effects,

instrumental drift, and isobaric overlap of some elemental

isotopes and molecular ions formed in the plasma, resulting

in suppression or enhancement of measured ion intensity.

An internal standard was added to minimize matrix effects

and instrumental drift. The isotopes measured were selected

to minimize isobaric overlap from other elements and

molecular species that might be present. Oxide overlaps

were subtracted by measuring the ratio of oxide to element

for single-element standards in each run and applying this

ratio to each sample.

RESULTS AND DISCUSSION

The values obtained for triplicate analyses of the eight

Argonne Premium Coal reference samples digested using

the sinter method are given in table 1. The values obtained

for triplicate analyses of the eight Argonne Premium Coal

reference samples prepared by using the acid digestion

method are given in table 2. 

The wide elemental coverage and the low limits of

determination of the ICAP-MS technique make it a worthwhile tool for the analysis of coal ash. The accuracy and

precision of the methods are adequate for the determination

of trace elements in coal ash. Tables 3–6 show values determined by ICAP-MS on solutions obtained by the two dissolution methods of the ash of National Institute of Standards

and Technology (NIST) reference standard materials 1632b

(coal) and 1633a (coal fly ash). The tables compare values

obtained in this study with the reference values. These comparisons show that reasonable accuracy is achieved by these

methods. Unfortunately, many elements determined have

not been reported for these reference materials, so accuracy
Table 1. Concentrations of rare earth and other elements determined by triplicate ICAP-MS analyses of eight Argonne Premium Coal 

dissolved by the sinter method. 

[All concentrations are in parts per million. ICAP-MS, inductively coupled argon plasma-mass spectrometry] 

Sample no. La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb 

UF PC-1-1 ........ 55 111 13.5 53 10.9 2.4 10 1.6 10.2 1.9 5.4 1.0 5.5 UF PC-1-2 ........ 60 128 14.5 55 11.2 2.6 12 1.8 10.9 2.3 6.2 1.1 5.8 UF PC-1-3 ........ 63 136 14.9 58 12.2 2.5 11 1.8 12.2 2.4 6.2 1.1 6.8 WY PC-2-1....... 47 94 10.8 43 8.3 1.8 7.6 1.2 7.4 1.4 4.1 .78 3.8 WY PC-2-2....... 44 90 10.2 40 7.6 1.9 7.2 1.2 8.3 1.6 3.7 .70 4.2 WY PC-2-3....... 51 100 11.7 44 8.9 2.2 8.8 1.3 8.8 1.6 4.7 .79 5.2 IL PC-3-1.......... 36 80 8.8 34 6.6 1.4 6.2 .84 6.3 1.2 3.4 .54 3.2 IL PC-3-2.......... 37 81 9.3 35 6.7 1.2 5.4 .94 5.6 1.0 2.9 .60 3.2 IL PC-3-3.......... 30 67 7.3 28 5.3 1.1 5.0 .72 4.9 .91 2.6 .48 3.2 PITT PC-4-1..... 52 116 12.8 51 9.9 1.8 8.4 1.2 8.4 1.7 4.1 .79 4.8 PITT PC-4-2..... 50 112 12.1 46 8.2 2.0 7.6 1.3 8.4 1.6 4.0 .78 4.5 PITT PC-4-3..... 50 106 11.6 44 8.8 1.8 7.4 1.2 8.7 1.5 4.3 .75 4.7 POC PC-5-1...... 113 227 26.1 104 19.9 4.1 20 3.2 22.2 4.3 11.3 1.8 10.9 POC PC-5-2...... 106 212 24.5 93 18.2 4.0 20 3.1 20.1 3.9 10.4 1.8 10.8 POC PC-5-3...... 102 206 22.7 90 18.2 3.9 18 2.9 19.4 3.9 10.1 1.8 10.7 UT PC-6-1 ........ 52 97 11.4 46 7.9 1.7 7.6 1.1 7.1 1.3 3.7 .63 4.1 UT PC-6-2 ........ 56 105 12.1 46 8.2 1.9 8.3 1.3 7.5 1.4 4.2 .72 4.3 UT PC-6-3 ........ 54 102 12.1 45 8.5 1.9 8.4 1.2 7.5 1.4 4.2 .68 4.6 WV PC-7-1....... 86 184 19.9 75 14.0 3.1 12 1.9 12.6 2.5 6.9 1.2 7.4 WV PC-7-2....... 92 198 22.1 82 15.2 3.2 14 2.2 14.3 2.8 6.8 1.4 8.6 WV PC-7-3....... 90 191 20.8 74 14.1 3.2 11 2.0 13.7 2.5 6.9 1.3 7.9 ND PC-8-1........ 22 43 4.3 16 2.8 .56 3.4 .50 3.8 .73 2.0 < .5 2.2 ND PC-8-2........ 24 44 4.9 17 2.7 .55 2.8 .50 3.7 .73 2.4 < .5 2.6 ND PC-8-3........ 21 42 4.4 15 2.5 .61 3.0 .55 3.4 .71 2.3 < .5 2.4 
Table 2. Concentrations of trace elements determined by triplicate ICAP-MS analyses of eight Argonne Premium Coal samples that w

the acid digestion method. [All concentrations are in parts per million. ICAP-MS, inductively coupled argon plasma-mass spectrometry] Sample no. Ag As Au Bi Cd Cs Ga Ge Mo Nb Pb Rb Sb S

UF PC-1-1 ........ 2.7 122 < 3 0.89 0.97 13.7 40.4 32.5 22.4 19 57 166 3.8 7UF PC-1-2 ........ 3.0 118 < 3 .89 1.6 13.5 38.6 31.8 16.6 17 57 160 3.4 7UF PC-1-3 ........ 4.6 119 < 3 .83 .98 13.8 39.6 32.4 16.5 18 55 163 3.7 7WY PC-2-1....... 2.0 34 <3 .65 1.2 2.4 21.9 4.2 6.1 16 19 21.2 1.8 3WY PC-2-2....... 2.4 31 <3 .65 1.3 2.4 21.4 4.2 5.8 15 19 21.2 1.8 3WY PC-2-3....... 3.9 22 <3 .58 1.7 2.2 24.0 4.5 6.3 18 18 21.2 2.2 3IL PC-3-1.......... 2.7 22 <3 .55 4.1 8.8 21.3 50.0 44.7 12 53 96.4 4.5 4IL PC-3-2.......... 3.8 24 <3 .54 4.7 8.8 22.5 53.2 34.4 14 54 99.3 5.0 4IL PC-3-3.......... 4.9 25 <3 <.5 5.8 8.3 22.4 52.4 37.4 15 50 95.9 5.2 4PITT PC-4-1..... 2.0 78 <3 1.3 1.1 8.7 34.5 12.3 7.7 17 41 87.0 2.0 6PITT PC-4-2..... 3.2 83 <3 1.3 .96 8.8 35.2 13.3 7.9 18 43 87.7 2.2 6PITT PC-4-3..... 4.8 89 <3 1.2 1.4 8.7 37.4 15.1 8.4 20 40 90.2 2.3 6POC PC-5-1...... 2.6 176 <3 .92 .64 4.3 32.1 4.4 49.3 19 34 38.5 5.4 6POC PC-5-2...... 4.2 185 <3 .98 1.0 4.3 33.9 5.1 50.0 20 32 39.8 5.5 6POC PC-5-3...... 6.0 198 <3 1.0 1.7 4.1 35.7 6.8 53.8 25 31 41.2 6.1 7UT PC-6-1........ 2.1 7.2 <3 .77 1.4 3.1 20.6 4.1 8.9 11 31 21.9 1.9 3UT PC-6-2........ 3.6 <1 <3 .78 1.7 3.1 21.5 5.1 9.0 12 32 22.8 1.9 3UT PC-6-3........ 4.2 <1 <3 .75 1.9 3.0 22.8 5.5 9.8 14 32 23.6 2.0 3WV PC-7-1....... 3.6 32 <3 1.2 .26 12.3 45.8 8.2 6.3 29 61 178 2.7 9WV PC-7-2....... 6.4 34 <3 1.2 .23 12.2 49.6 8.8 6.6 31 65 189 2.8 9WV PC-7-3....... 9.1 37 <3 1.2 .37 12.0 49.8 8.8 6.8 34 64 188 3.2 9ND PC-8-1........ .95 17 <3 < 0.5 .31 1.1 12.7 3.4 4.1 7.8 20 14.4 1.4 2ND PC-8-2........ 1.6 7.4 <3 < 0.5 .45 1.0 12.0 3.9 4.4 8.4 8.8 14.8 1.5 3ND PC-8-3........ 2.3 <1 <3 < 0.5 .52 1.1 12.1 4.3 4.6 8.8 16 15.4 2.0 5
INDUCTIVELY COUPLED ARGON PLASMA-MASS SPECTROMETRY 49

Table 4. Comparison of reference values with mean

concentrations of trace elements determined by 23 replicate

ICAP-MS analyses of NIST standard reference material

1633a (coal fly ash) that was dissolved by the acid digestion

method.

[All concentrations are in parts per million (ppm). The reference

values for NIST standard reference material 1633a (coal fly ash) are

from National Bureau of Standards (1979). ICAP-MS, inductively

coupled argon plasma-mass spectrometry; NIST, National Institute

of Standards and Technology, formerly the National Bureau of

Standards; RSD, relative standard deviation (in percent); STD,

standard deviation (in parts per million); —, no data] 

Element

Ref.

value

(ppm)

This study

Mean

(ppm)

STD

(ppm)

RSD

(%)

Ag............... — 2.3 1.7 76

As ............... 145 172 9.1 5

Au............... — <3.0 — —

Bi ................ — 1.3 .2 13

Cd ............... 1 1.2 .2 15

Cs................ 11 10 1.9 19

Ga ............... 58 65 5.3 8

Ge ............... 33.9 39 2.5 6

Mo .............. 29 35 1.0 3

Nb............... — 30 2.5 8

Pb................ 72.4 83 7.4 9

Rb ............... 131 148 30.7 21

Sb................ 6.8 7.3 .5 7

Sn................ 10 9.2 .7 7

Te................ — <.5 — —

Tl ................ 5.7 6.5 .6 9

U................. 10.2 12 .9 8

Table 3. Comparison of reference values with mean

concentrations of trace elements determined by 23 replicate

ICAP-MS analyses of NIST standard reference material

1632b (coal) that was ashed and dissolved by the acid

digestion method.

[All concentrations are in parts per million (ppm). The reference

values for NIST standard reference material 1632b (coal) are from

National Bureau of Standards (1985). ICAP-MS, inductively coupled argon plasma-mass spectrometry; NIST, National Institute of

Standards and Technology, formerly the National Bureau of Standards; RSD, relative standard deviation (in percent); STD, standard

deviation (in parts per million); —, no data] 

Element

Ref.

value

(ppm)

This study

Mean

(ppm)

STD

(ppm)

RSD

(%)

Ag................ — 1.7 1.3 75

As ................ 54.7 63 4.2 7

Au................ — <3.0 — —

Bi................. — 1.7 .2 14

Cd................ — 1.1 .3 28

Cs ................ 6.5 6.0 1.4 24

Ga................ — 44 3.1 7

Ge................ — 33 4.5 13

Mo............... 13.2 13 .5 4

Nb................ — 24 1.3 5

Pb ................ 54.0 63 8.2 13

Rb................ 74.3 75 21.2 28

Sb ................ — 3.6 .3 8

Sn ................ — 9.5 .5 5

Te................. — <.5 — —

Tl................. — 2.3 .3 12

U.................. 6.4 6.6 .6 8
50 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

cannot be estimated using these materials. Precision is given

as standard deviation and relative standard deviation for

each element determined in the reference materials. For

most elements, precision is better than 10 percent relative

standard deviation. Precision for some elements is poorer,

especially as detection limits are approached. Silver concentrations determined on solutions obtained by the acid digestion method have the most variation. The lack of precision

can be attributed to sampling variation as well as instrumental variation.

REFERENCES

Borsier, M., and Garcia, M., 1983, Analyse automatique d'echantillons geologiques par plasma ICP: Spectrochimica Acta, v.

38B, nos. 1/2, p. 123–127.

Crock, J.G., Lichte, F.E., and Briggs, P.H., 1983, Determination of

elements in National Bureau of Standards’ geological reference materials SRM 278 obsidian and SRM 688 basalt by

inductively coupled argon plasma-atomic emission spectrometry: Geostandards Newsletter, v. 7, no. 2, p. 335–340.

Lichte, F.E., Meier, A.L., and Crock, J.G., 1987, Determination of

the rare-earth elements in geological materials by inductively

coupled plasma mass spectrometry: Analytical Chemistry, v.

59, no. 8, p. 1150–1157.

National Bureau of Standards, 1979, National Bureau of Standards

certificate of analysis, standard reference material 1633a,

trace elements in coal fly ash: Washington, D.C., National

Bureau of Standards, 2 p.

———1985, National Bureau of Standards certificate of analysis,

standard reference material 1632b, trace elements in coal

(bituminous): Gaithersburg, Md., National Bureau of Standards, 5 p.

Table 6. Comparison of reference values with mean

concentrations of rare earth and other elements determined

by 22 replicate ICAP-MS analyses of NIST standard

reference material 1633a (coal fly ash) that was dissolved

by the sinter method.

[All concentrations are in parts per million (ppm). The reference

values for NIST standard reference material 1633a (coal fly ash) are

from National Bureau of Standards (1979). ICAP-MS, inductively

coupled argon plasma-mass spectrometry; NIST, National Institute

of Standards and Technology, formerly the National Bureau of

Standards; RSD, relative standard deviation (in percent); STD,

standard deviation (in parts per million); —, no data] 

Element

Ref.

value

(ppm)

This study

Mean

(ppm)

STD

(ppm)

RSD

(%)

La................ — 87.30 5.28 6.0

Ce................ 180.0 168.12 12.36 7.4

Pr................. — 19.16 1.32 6.9

Nd ............... — 75.71 4.91 6.5

Sm............... — 16.34 .82 5.0

Eu................ 4.0 3.97 .22 5.7

Gd ............... — 16.16 1.52 9.4

Tb................ — 2.51 .18 7.1

Dy ............... — 15.48 1.04 6.7

Ho ............... — 2.88 .16 5.5

Er ................ — 8.51 .44 5.1

Tm............... — 1.22 .08 6.7

Yb ............... — 7.65 .46 6.0

Hf................ 7.6 8.09 .82 10.2

Ta ................ — 2.14 .19 9.0

W ................ — 6.11 .52 8.5

Table 5. Comparison of reference values with mean

concentrations of rare earth and other elements determined

by 22 replicate ICAP-MS analyses of NIST standard

reference material 1632b (coal) that was ashed and

dissolved by the sinter method.

[All concentrations are in parts per million (ppm). The reference

values for NIST standard reference material 1632b (coal) are from

National Bureau of Standards (1985). ICAP-MS, inductively coupled argon plasma-mass spectrometry; NIST, National Institute of

Standards and Technology, formerly the National Bureau of Standards; RSD, relative standard deviation (in percent); STD, standard

deviation (in parts per million); —, no data] 

Element

Ref.

value

(ppm)

This study

Mean

(ppm)

STD

(ppm)

RSD

(%)

La................ 75.0 64.3 3.11 4.8

Ce................ 132.4 124.6 7.18 5.8

Pr................. — 13.6 .73 5.4

Nd ............... — 53.2 2.98 5.6

Sm............... 12.8 10.9 .65 6.0

Eu................ 2.5 2.5 .19 7.5

Gd ............... — 10.2 .84 8.3

Tb................ — 1.5 .11 7.0

Dy ............... — 9.4 .57 6.1

Ho ............... — 1.7 .11 6.4

Er ................ — 5.3 .36 6.8

Tm............... — .8 .07 8.6

Yb ............... — 5.0 .37 7.5

Hf................ 6.3 6.8 .55 8.1

Ta ................ — 2.0 .24 12.1

W ................ 7.1 6.8 .51 7.5
51

Determination of Mercury and Selenium in

Eight Argonne Premium Coal Samples by

Cold-Vapor and Hydride-Generation 

Atomic Absorption Spectrometry

By Richard M. O'Leary

ABSTRACT

The methods for the determination of mercury and

selenium in whole coal by cold-vapor atomic absorption

spectrometry (CVAAS) and hydride-generation atomic

absorption spectrometry (HGAAS) are described. The

Argonne Premium Coal samples were analyzed in triplicate

to determine the precision of the method. The averaged values ranged from 0.01 to 0.39 μg/g for mercury and 0.60 to

6.2 μg/g for selenium. Mercury and selenium were also

determined in standard reference materials from the

National Institute of Standards and Technology (NIST), the

Community Bureau of Reference (BCR) of the Commission

of the European Communities, the National Research Council of Canada (NRCC), and the U.S Geological Survey

(USGS). Results obtained by these methods were compared

with the published values to determine the accuracy of the

methods.

INTRODUCTION

Analytical techniques for the determination of mercury

and selenium in coal are increasing in importance. With the

passage of the 1990 Clean Air Act Amendments (CAAA),

the Environmental Protection Agency (EPA) has been given

the authority to set emission standards for a number of

potentially hazardous air pollutants (HAP’s) generated by a

number of specific combustion sources. Mercury, selenium,

and nine other elements present in coal are among the 189

pollutants identified as air toxins in the CAAA legislation.

Although their concentrations in coal are minor, they represent a potentially significant release of mercury and selenium to the environment because of the large tonnage of

coal burned in powerplants.

The most common instrumental technique for determining mercury is cold-vapor atomic absorption spectrometry (CVAAS). Some CVAAS techniques preconcentrate the

mercury using a gold amalgam, then thermally release the

mercury by inductively heating the gold; however, alternative techniques analyze the mercury vapor directly. Other

instrumental techniques include graphite furnace atomic

absorption spectroscopy (GFAAS), cold-vapor atomic fluorescence spectroscopy (CVAFS), and neutron activation

analysis (NAA). Various sample preparation procedures

include oxygen bomb combustion, direct coal combustion,

microwave digestion, and hotplate acid digestion.

In the procedure described here, a 0.150-g coal sample

was decomposed by a heated mixture of nitric and sulfuric

acids and vanadium pentoxide. The sample solution was

introduced to a continuous-flow CVAAS system, where it

was complexed and reduced with a solution of hydroxylamine hydrochloride and sodium chloride prior to further

reduction with stannous chloride. The mercury vapor was

then separated from the liquid in the phase separator before

entering the quartz cell for the determination of the mercury

concentration.

Like mercury, selenium can be determined by a number of different instrumental techniques such as GFAAS,

NAA, and hydride-generation atomic absorption spectrometry (HGAAS). Of the AAS techniques, hydride generation

is the technique of choice because it is relatively interference free as compared to GFAAS.

In the method used in this study, a 0.100-g sample of

pulverized coal was digested at 150–200°C with a mixture

of concentrated sulfuric, nitric, and perchloric acids until a

clear to yellow solution was reached. After the addition of 6

M hydrochloric acid, the solution was allowed to set to permit the selenium to reduce the Se+3 state. The diluted solution was then introduced by way of an autosampler and

peristaltic pump to a Varian VGA-76 hydride generator coupled to an atomic absorption spectrophotometer. The sample

solution was then mixed with concentrated hydrochloric

acid and 0.35 percent sodium borohydride, and the resultant

selenium hydride was then transported with argon gas to an

air-acetylene flame-heated quartz cell for atomization and

estimation of the selenium concentration. 
52 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

PROCEDURE FOR MERCURY

Approximately (scooped) 0.1 g vanadium pentoxide,1,2

1.5 mL concentrated sulfuric acid, and 3.5 mL concentrated

nitric acid were added to 0.150 g of whole coal in a

16¥150-mm disposable test tube and mixed. The test tube

was placed in an aluminum heating block and covered with

a watch glass. The temperature was ramped gradually to

150°C over a 2-hour period. The tube was heated overnight

at this temperature and then removed and allowed to cool.

The sample was diluted to 15 mL with water, capped, and

shaken for 5 minutes. It was then centrifuged at 1,000 rpm

(revolutions per minute) for 5 minutes, and approximately

1Unless otherwise noted, all chemicals used in the mercury determinations are of Baker “Instra Analyzed” quality or are labeled “Suitable for

mercury determinations,” and the water is deionized. 2Some brands of vanadium pentoxide (reagent grade) contain trace

amounts of mercury and need to be roasted at 500°C prior to use.

12 mL of solution was transferred to a 16¥100-mm disposable test tube.

The mercury was determined by using a continuousflow-through CVAAS system (fig. 1) as described by

Kennedy and Crock (1987). The test tube containing the

sample solution was placed in the autosampler. The sample

solution was fed from the autosampler by a peristaltic pump

into a continuous-flow system, where it was mixed with a

reducing-complexing solution of 3 percent hydroxylamine

hydrochloride (reagent grade) and 3 percent sodium chloride (reagent grade) in 10 percent sulfuric acid. Next, the

sample was further reduced with a 10 percent stannous

chloride in 10 percent hydrochloric acid. The sample then

entered a phase separator where the mercury gas passed

through the flow-through cell of the AAS for measurement

and the liquid was discharged to waste. The absorbance

indicating the mercury concentration was recorded on a

strip chart, and peak heights were measured. The operating

conditions for the AAS are shown in table 1.

The samples were compared against a calibration curve

generated by analyzing standards in the 1- to 15-μg/L range.

The calibration standards were made by dilution of a 1.47-

μg/mL mercury solution (standard reference material

(SRM) 1641c) obtained from NIST (National Institute of

Standards and Technology). The calibration standards contained a final concentration of 3.7 M nitric acid, 1.8 M sulfuric acid, and 0.5 percent (w/v, weight per volume) sodium

dichromate (reagent grade).

PROCEDURE FOR SELENIUM

The method used for determining selenium is a modification of that described by Aruscavage (1977). Twenty

milliliters of concentrated hydrochloric acid3 and 2 mL concentrated sulfuric acid were added to 0.100 g of whole coal

3Unless otherwise noted, all chemicals used in the selenium determinations are Baker “Instra Analyzed” or of equal purity, and the water is

deionized.

Table 1. Operating conditions for determination of mercury

and selenium by cold-vapor atomic absorption spectrometry

(CVAAS) and hydride-generation AAS (HGAAS), respectively. 

Hg Se

Source................................. Hg hollow 

cathode lamp.

Electrodeless 

discharge 

lamp (EDL).

Slit ...................................... 0.7 nm 0.7 nm

Wavelength ......................... 253.7 nm 196.0 nm

Quartz cell temperature ...... 100°C 2,000°C

Mode................................... Absorbance Absorbance

Recorder ............................. 2 mV, 5 mm/

min

10 mV, 5 mm/

min

AA recorder mode .............. TC3 TC3

Sensitivity (peak height)..... 1 μg/L = 19 mm 10 μg/L = 72 mm

Figure 1. Continuous-flow cold-vapor atomic absorption

spectrometry (CVAAS) manifold for determining mercury. A,

Autosampler, 8 mL/min; B, 8-channel peristaltic pump; C, 1

percent nitric acid wash, 7 mL/min; D, air, 48 mL/min; E,

complexing-reducing solution, 3.5 mL/min; F, 20-turn mixing

coil; G, stannous chloride solution, 3.5 mL/min; H, 80-turn mixing

coil; I, liquid-gas separator; J, liquid to waste; K, flow-through cell

in atomic absorption spectrophotometer; L, strip chart recorder. 
COLD-VAPOR AND HYDRIDE-GENERATION ATOMIC ABSORPTION SPECTROMETRY 53

Table 2. Mercury (Hg) and selenium (Se) contents in eight

Argonne Premium Coals determined by cold-vapor and hydridegeneration atomic absorption spectrometry (CVAAS and

HGAAS), respectively.

[All values in micrograms per gram (mg/g)] 

Sample ID

Hg, CVAAS Se,

HGAAS 1st day 2d day Average

UF PC-1-1........ 0.38 0.39 — 2.3

UF PC-1-2........ .37 .40 — 2.0

UF PC-1-3........ .44 .37 — 1.5

Average........ — — 0.39 1.9

WY PC-2-1...... .13 .11 — 1.8

WY PC-2-2...... .12 .13 — 2.8

WY PC-2-3...... .11 .14 — 2.5

Average........ — — .12 2.4

IL PC-3-1......... .09 .10 — 4.1

IL PC-3-2......... .10 .08 — 4.0

IL PC-3-3......... .09 .09 — 4.3

Average........ — — .09 4.1

PITT PC-4-1 .... .15 .16 — 1.8

PITT PC-4-2 .... .17 .17 — 1.6

PITT PC-4-3 .... .15 .16 — 1.6

Average........ — — .16 1.7

POC PC-5-1..... .06 .06 — 2.9

POC PC-5-2..... .06 .06 — 2.9

POC PC-5-3..... .06 .05 — 3.1

Average........ — — .06 3.0

UT PC-6-1 ....... .02 .01 — 1.2

UT PC-6-2 ....... .01 .01 — 1.3

UT PC-6-3 ....... .01 .01 — 1.3

Average........ — — .01 1.3

WV PC-7-1...... .08 .08 — 6.1

WV PC-7-2...... .07 .08 — 5.6

WV PC-7-3...... .10 .10 — 6.9

Average........ — — .08 6.2

ND PC-8-1....... .08 .08 — .60

ND PC-8-2....... .08 .08 — .60

ND PC-8-3....... .07 .08 — .60

Average........ — — .08 .60

Figure 2. Continuous-flow hydride-generation atomic absorption spectrometry (HGAAS) manifold for determining selenium.

A, Autosampler, 8 mL/min; B, 4-channel peristaltic pump; C,

deionized water wash, 8 mL/min; D, concentrated hydrochloric

acid, 1 mL/min; E, sodium borohydride solution, 1 mL/min; F,

nitrogen purge gas, 90 mL/min; G, liquid-gas phase separator; H,

liquid to waste; I, heated quartz furnace in atomic absorption spectrophotometer; J, strip chart recorder.

in a 250-mL Erlenmeyer flask. After the mixture was

allowed to stand overnight, 3 mL of perchloric acid (redistilled) was added. A claw refluxer was added to the flask,

and the solution was heated on a hotplate at 150–200°C for

30 minutes. The refluxers were removed, and heating of the

solution was continued until the development of dense

white fumes and a clear to yellow solution. The solution

then was removed from the hotplate. When the solution was

cool, 25 mL of 6 M hydrochloric acid was added, and the

solution was allowed to stand for 30 minutes to permit the

selenium to reduce to the Se+3 state. The contents of the

flask were transferred to a 60-mL polyethylene bottle and

diluted to 55 g with water.

The selenium was determined by the HGAAS system

using a Varian VGA-76 hydride generator coupled to a Perkin-Elmer atomic absorption spectrophotometer (fig. 2).

The solution was transferred to 13¥100-mm test tubes and

placed in an autosampler. The sample solution was then fed

from the autosampler to the hydride-generation system by a

peristaltic pump, where it was mixed with concentrated

hydrochloric acid and 0.35 percent sodium borohydride.

The selenium hydride was then transported with argon gas

to the air-acetylene flame-heated quartz furnace of the AAS

for atomization. The absorbance indicating the selenium

concentration was registered on a strip chart recorder, and

peak heights were measured. The operating conditions for

the AAS are shown in table 1.

The samples were compared against a calibration curve

generated by analyzing standards in the 5- to 20-μg/L range.

The calibration standards were made by dilution of a commercially prepared 10-μg/g selenium standard in 10 percent

HCl. The calibration standards contained a final concentration of 3 M hydrochloric acid and 0.72 M sulfuric acid.

DISCUSSION

The eight Argonne Premium Coal samples were analyzed for selenium in triplicate on one day and for mercury

in triplicate on two nonconsecutive days. All analyses were

performed in the U.S. Geological Survey laboratory in Denver, Colo. The averaged values for mercury range from 0.01

to 0.39 μg/g, and the averaged values for selenium range

from 0.60 to 6.2 μg/g as shown in table 2. As a measure of

quality control, several standard reference materials were
54 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 4. Comparison of recommended values of selenium concentrations in standard reference materials with mean

concentrations determined in this study by hydride-generation atomic absorption spectrometry (HGAAS).

[Column headings: RV, recommended value of selenium concentration from the references A–C; SDEV, standard deviation; %RSD,

relative standard deviation, in percent; %R, percent recovery, which compares the values obtained by HGAAS in this study with the recommended values; mg/g, micrograms per gram. Sources: NIST, U.S. National Institute of Standards and Technology, formerly the

National Bureau of Standards (NBS); USGS, U.S. Geological Survey. References: A, NBS, 1978b; B, Stephen A. Wilson, USGS, oral

commun., 1994; C, Eric P. Welsch, USGS, written commun., 1991] 

Standard Source Reference Description RV

(mg/g)

This study, HGAAS

%R Mean

(mg/g)

SDEV

(mg/g) %RSD

SRM 1635 .............. NIST A Coal 0.9 0.95 0.10 11 108

CLB-1..................... USGS B Coal 2.1 2.5 .2 8 119

ALF ........................ USGS C Alfalfa .19 .18 .02 11 95

Table 3. Comparison of recommended values of mercury concentrations in standard reference materials with mean

concentrations determined in this study by cold-vapor atomic absorption spectrometry (CVAAS).

[Column headings: RV, recommended value of mercury concentration from the references A–E; SDEV, standard deviation; %RSD, relative

standard deviation, in percent; %R, percent recovery, which compares the values obtained by CVAAS in this study with the recommended values; mg/g, micrograms per gram. Sources: NIST, U.S. National Institute of Standards and Technology, formerly the National Bureau of Standards (NBS); NRCC, National Research Council of Canada; USGS, U.S. Geological Survey; BCR, Community Bureau of Reference of the

Commission of the European Communities. References: A, Lengyel and others, 1994; B, NBS, 1974; C, NBS, 1978a; D, Govindaraju, 1989; E,

Griepink and others, 1986] 

Standard Source Reference Description RV

(mg/g)

This study, CVAAS

%R Mean

(mg/g)

SDEV

(mg/g) %RSD

SRM 1632b............. NIST A Coal 0.077 ± 0.017 0.068 0.005 7.4 88

SRM 1632............... NIST B Coal .12 ± 0.02 .091 .011 12 76

SRM 1632a............. NIST C Coal .13 ± 0.03 .119 .007 5.9 91

MESS-1 .................. NRCC D Marine sediment .171 .175 .02 11 102

SDO-1..................... USGS D Shale .19 .182 .011 6 96

CRM 181 ................ BCR E Coal .138 ± 0.011 .143 .005 3.5 104

also analyzed for mercury and selenium by CVAAS and

HGAAS, and the results are reported in tables 3 and 4,

respectively. The standards chosen were coal, shale, a plant,

and marine sediment. The tables compare the published values of the reference materials with the mean and standard

deviation obtained from these methods.

The lower limits of determination for mercury and

selenium are 0.01 and 0.1 mg/g, respectively, which are

based on three times the standard deviation of the blank.

The precision of the mercury values is in the range of 3.5 to

12 percent relative standard deviation (%RSD), and the

accuracy, based on the percent recovery (%R), which compares this method’s values with the recommended values

(RV), ranges from 76 to 104 percent (table 3). The precision

of the values for selenium is in the range of 8 to 11 %RSD,

and the accuracy or %R ranges from 95 to 119 percent of

the recommended values (table 4). Both methods offer a

technique that is simple and rapid, and both are applicable

to a wide range of organically based samples.

REFERENCES

Aruscavage, Philip, 1977, Determination of arsenic, antimony, and

selenium in coal by atomic absorption spectrometry with a

graphite tube atomizer: U.S. Geological Survey Journal of

Research, v. 5, no. 4, p. 405–408.

Govindaraju, K., ed., 1989, 1989 Compilation of working values

and sample description of 272 geostandards: Geostandards

Newsletter, v. 13, Special Issue, p. 67.

Griepink, B., Colinet, E., and Wilkinson, H.C., 1986, The certification of the contents (mass fraction) of carbon, hydrogen,

nitrogen, chlorine, arsenic, cadmium, manganese, mercury,

lead, selenium, vanadium and zinc in three coals; gas coal

CRM No. 180, coking coal CRM No. 181, and steam coal

CRM No. 182: Commission of the European Communities,
COLD-VAPOR AND HYDRIDE-GENERATION ATOMIC ABSORPTION SPECTROMETRY 55

Community Bureau of Reference (Brussels), Report EUR

10366 EN, 170 p.

Kennedy, K.R., and Crock, J.G., 1987, Determination of mercury

in geological materials by continuous-flow, cold-vapor,

atomic absorption spectrophotometry: Analytical Letters, v.

20, p. 899–908.

Lengyel, J., Jr., DeVito, M.S., and Bilonick, R.A., 1994, Interlaboratory and intralaboratory variability in the analysis of mercury in coal: Library, Pa., Consol Inc.

National Bureau of Standards, 1974, National Bureau of Standards

certificate of analysis, standard reference material 1632, trace

elements in coal (bituminous): Washington, D.C., National

Bureau of Standards, 2 p.

———1978a, National Bureau of Standards certificate of analysis, standard reference material 1632a, trace elements in coal

(bituminous): Washington, D.C., National Bureau of Standards, 2 p.

———1978b, National Bureau of Standards certificate of analysis, standard reference material 1635, trace elements in coal

(subbituminous): Washington, D.C., National Bureau of

Standards, 2 p.
57

Determination of Carbon, Hydrogen, and Nitrogen in 

Eight Argonne Premium Coal Samples by 

Using a Gas Chromatographic Analyzer with a

Thermal Conductivity Detector

By Carol J. Skeen and Zoe A. Brown

ABSTRACT

The carbon, hydrogen, and nitrogen contents of eight

Argonne Premium Coals were determined by using the Perkin-Elmer 240B elemental gas chromatographic (GC) analyzer with a thermal conductivity detector (TCD). Precision

for the analysis of these samples is within the accepted 0.1

percent relative standard deviation. The carbon content

ranged from 56 to 86 percent; the hydrogen content ranged

from 3.7 to 5.6 percent; and the nitrogen content ranged

from 0.93 to 2.2 percent. Because these ranges are typical

for coals, the NIST (National Institute of Standards and

Technology) 1635 coal standard reference material was chosen as the control standard to evaluate the accuracy of the

method.

INTRODUCTION

Analysis of a substance for carbon, hydrogen, and

nitrogen generally requires drastic treatment of the material

in order to convert the elements into a form readily determined by routine analytical techniques. A common way to

convert the carbon, hydrogen, and nitrogen to gaseous products is to carry out an oxidation in a quartz combustion tube

through which is forced a stream of carrier gas. The stream

transports the volatile products to the part of the apparatus

where they can be separated for measurement.

The combustion train is packed with silver compounds

to remove any halogen and sulfur compounds generated,

because these compounds interfere with the determination

of carbon dioxide and water. Before reaching the combustion train, the helium and oxygen flow through scrubbers

packed with colorcarb and anhydron to remove extraneous

contaminants.

The Perkin-Elmer 240B elemental gas chromatographic analyzer with a thermal conductivity detector gives

excellent results for finely ground, dry materials, especially

materials high in organic matter, with the following concentration ranges: 0.1–100 percent for carbon, 0.01–12 percent

for hydrogen, and 0.10–18 percent for nitrogen.

ANALYTICAL PROCEDURE

Standard operating procedures for use of the PerkinElmer 240B and a revised statistical computer program

(Abramowitz, 1964) were implemented for the analysis of

the eight Argonne Premium Coals. Oxygen was the combustion gas, and helium was the carrier gas. The instrument was

calibrated by oxidizing three samplings of standard acetanilide, all of approximately the same weight (1.0 to 1.3 mg).

The furnace temperatures were 950°C for the combustion

tube and 650°C for the reduction tube. The sample weights

used were between 1.0 mg and 1.3 mg.

The NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards) 1635

coal standard reference material (SRM) was analyzed as a

control standard at the same time as the last three premium

coals. Table 1 shows these results along with the NIST SRM

Table 1. Comparison of published concentrations of carbon,

hydrogen, and nitrogen in NIST standard reference material 1635

(coal) with concentrations determined in this study by using a gas

chromatographic analyzer with a thermal conductivity detector

(GC/TCD).

[All concentrations are in weight percent. NIST, National Institute of Standards and Technology, formerly the National Bureau of Standards (NBS)] 

Element This study,

GC/TCD NBS (1978) Gladney and others (1987)

C ................ 63.0 62.2 ± 1.8 62.6

H ................ 3.98 3.96 ± 0.03 4.07

N ................ 1.5 1.0 ± 0.1 1.26
58 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

values (National Bureau of Standards, 1978) and the analytical values of Gladney and others (1987). 

RESULTS AND DISCUSSION

A study was made to ascertain the detection limits of

this method (Filby and others, 1985). By diluting pure acetanilide with ultra-pure silica to prepare three analytical standards— (1) 7.1 percent C, 0.67 percent H, and 1.04 percent

N, (2) 0.71 percent C, 0.067 percent H, and 0.104 percent

N, and (3) 0.071 percent C, 0.0067 percent H, and 0.010

percent N—and by using acetanilide undiluted (71.07 percent C, 6.71 percent H, and 10.36 percent N), the lowest

detection limits were calculated to be 0.1 percent C, 0.01

percent H, and 0.10 percent N. The experiment using various sampling weights also validated that the analytical

curves were linear from the detection limit to the highest

standard.

The results of these coal analyses were compared with

the published data for the Argonne Premium Coal Sample

Program (Vorres, 1990) for carbon, hydrogen, and nitrogen

determined on dried whole coals. The values were in good

agreement with all the coals except for the carbon values for

the subbituminous coal (WY) and the lignite (ND). To verify the accuracy of this paper’s results, analyses of these two

Table 2. Comparison of published concentrations of carbon, hydrogen, and nitrogen in eight Argonne

Premium Coals with concentrations determined in this study by using a gas chromatographic analyzer with a

thermal conductivity detector (GC/TCD).

[All concentrations are in weight percent] 

Coal samples

C HN

This study Vorres (1990) This study Vorres (1990) This study Vorres (1990)

UF PC-1-1 ...... 77 4.6 2.2

UF PC-1-2 ...... 76 4.7 1.8

UF PC-1-3 ...... — — —

UF Average..... 77 74.23 4.7 4.08 2.0 1.35

WY PC-2-1..... 60 4.4 1.2

WY PC-2-2..... 60 4.6 1.2

WY PC-2-3..... — — —

WY Average ... 60 68.43 4.5 4.88 1.2 1.02

WY Repeat ..... 61

IL PC-3-1........ 64 4.5 1.6

IL PC-3-2........ 65 4.5 1.8

IL PC-3-3........ — — —

IL Average ...... 65 65.65 4.5 4.23 1.7 1.16

PITT PC-4-1... 74 5.0 2.2

PITT PC-4-2... 75 5.0 2.0

PITT PC-4-3... — — —

PITT Average . 75 75.50 5.0 4.83 2.1 1.49

POC PC-5-1.... 86 4.4 1.9

POC PC-5-2.... 86 4.3 2.0

POC PC-5-3.... — — —

POC Average .. 86 86.71 4.4 4.23 2.0 1.27

UT PC-6-1...... 72 5.5 1.6

UT PC-6-2...... 74 5.5 1.8

UT PC-6-3...... 74 5.6 1.4

UT Average..... 73 76.89 5.5 5.49 1.6 1.50

WV PC-7-1..... 64 4.3 1.3

WV PC-7-2..... 65 4.3 1.4

WV PC-7-3..... 66 4.2 1.4

WV Average ... 65 66.20 4.3 4.21 1.4 1.25

ND PC-8-1...... 56 3.8 1.2

ND PC-8-2...... 57 3.7 1.0

ND PC-8-3...... 57 3.7 .93

ND Average .... 57 65.85 3.7 4.36 1.0 1.04

ND Repeat...... 57
USING A GAS CHROMATOGRAPHIC ANALYZER WITH A THERMAL CONDUCTIVITY DETECTOR 59

samples were repeated with special attention given to

proper drying of the samples before analysis. The carbon

values obtained by the repeat analyses, 61 percent for WY

and 57 percent for ND, are in agreement with values

obtained by the initial analyses. Table 2 shows the results

for the replicate analyses of these coals, the repeats, and

Vorres’ published data. 

The differences between the results from Argonne

National Laboratories (Vorres, 1990) and the data reported

in this paper could be due to oxidation of these two coals.

Argonne went to great lengths to seal these coals in an oxygen-free environment. Because analysis in the U.S. Geological Survey laboratories was not done immediately after the

ampoules were opened, it is likely that the subbituminous

coal and the lignite oxidized. Bituminous coals are characteristically more stable.

The precision of this method is within the 0.1 percent

relative standard deviation, which is well within the

accepted deviation for this type of analysis. The analysis of

NIST 1635 indicates that the accuracy is also excellent.

REFERENCES

Abramowitz, M., 1964, Elementary analytical methods, in

Abramowitz, M., and Stegun, I.A., eds., Handbook of mathematical functions—National Bureau of Standards Applied

Mathematics Series 55: Washington, D.C., U.S. Government

Printing Office, chap. 3, p. 18.

Filby, R.H., and others, 1985, Evaluation of geochemical standard

reference materials for microanalysis: Analytical Chemistry,

v. 57, no. 2, p. 551–555.

Gladney, E.S., O’Malley, B.T., Roelundts, J., and Gilly, T.E., 1987,

Composition of elemental concentration data for NIST clinical, biological, geological and environmental standard reference materials: National Institute of Standards and

Technology Special Publication 260–111, p. 21–22.

National Bureau of Standards, 1978, National Bureau of Standards

certificate of analysis, standard reference material 1635,

trace elements in coal (subbituminous): Washington, D.C.,

National Bureau of Standards, 2 p.

Vorres, K.S., 1990, The Argonne Premium Coal Sample Program:

Energy and Fuels, v. 4, no. 5, p. 420–426.
61

Compilation of Multitechnique Determinations of 

51 Elements in 8 Argonne Premium Coal Samples

By Curtis A. Palmer and Sarah A. Klizas

ABSTRACT

Eight Argonne Premium Coal samples were analyzed

by the U.S. Geological Survey. The concentrations of 51

elements were determined by two or more techniques on

each sample. The analyses were performed by energy- and

wavelength-dispersive X-ray fluorescence spectrometry,

instrumental neutron activation analysis, inductively coupled argon plasma-atomic emission spectroscopy, atomic

absorption spectrometry, inductively coupled argon plasmamass spectrometry, and direct-current arc spectrographic

analysis. All data are compiled on a whole-coal basis for

ease of comparison. The ash values are also included so that

data can be converted to an ash basis if desired.

INTRODUCTION

Although the eight Argonne Premium Coal samples

analyzed in this study are not defined as “reference

standards” by Argonne National Laboratories, they are

extremely important because of the care that has been taken

in collection, preparation, and storage. A detailed description of the background information for these samples has

been reported by Vorres (1990, 1993). However, these samples have not been widely analyzed for trace elements. The

analytical laboratories of the U.S. Geological Survey analyzed these samples to further characterize them and to provide a foundation for a trace-element data base.

Most quantitative techniques used for elemental analyses of geologic samples offer high levels of precision and

accuracy for selected elements in certain types of samples

over specific ranges of concentrations, but all analytical

techniques have certain characteristic limitations. For example, matrix-induced spectral interferences can result in

incorrect determinations of trace elements. Even if properly

corrected, these interferences may lead to reduced sensitivity or precision for a given element. Generally, the concentrations of elements determined by another technique on the

same matrix will not be affected by the same interferences. 

A multitechnique approach for major- and trace-element analysis was taken to provide the high degree of reliability desired to characterize these materials. In addition,

this information may be useful in evaluating data from a single technique for coal analysis for laboratories that do not

have all techniques available. Semiquantitative analytical

techniques, although not offering the precision or accuracy

of the quantitative techniques, rapidly provide a large volume of data. Some of the data obtained by these low-precision techniques are not easily obtained by quantitative

methods, but can be useful in the overall characterization of

these materials.

This paper (1) summarizes the results of the multitechnique analyses of the Argonne Premium Coals, (2) discusses

some discrepancies in the data, and (3) determines “recommended values” or “best averages” depending on the precision of the data. Each of the eight Premium Coal samples

has been analyzed in triplicate for 68 elements. Fifty-one

elements were determined by more than one technique.

Although up to seven different techniques were used for

some elements, there are not enough high-precision data to

recommend values for all elements in all coals using common criteria for establishing such values (Kane and others,

1990). Therefore, modified criteria were designed for this

data set. They allowed definition of “recommended values”

on slightly less than half of the elements included in the data

set.

SAMPLES AND TECHNIQUES

Three splits of each of the Argonne Premium Coal

samples were analyzed by multiple techniques. The samples

and the sample identification protocol are described in this

volume by Palmer (see p. 1). 

Ideally, solid samples of the whole coal would be analyzed by instrumental techniques because this type of analysis avoids problems caused by volatilization of elements

during ashing and problems caused by incomplete sample

dissolution. The procedures used for determining element
62 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

concentrations instrumentally on the whole coal are discussed in this volume in the following papers:

Author Procedure

Fletcher and Skeen .. Quantitative DCAES, direct-current

arc atomic emission spectrography

Evans and others ..... WDXRF, wavelength-dispersive Xray fluorescence spectrometry

EDXRF, energy-dispersive XRF

Palmer ..................... INAA, instrumental neutron activation analysis

O’Leary ................... CVAAS and HGAAS, cold-vapor

and hydride-generation atomic

absorption spectrometry

Skeen and Brown .... Gas chromatographic analysis with a

thermal conductivity detector

Although the sensitivity of INAA was acceptable for most

of the 29 elements determined, the sensitivities of the other

whole-coal procedures were marginal for many elements.

Therefore, coal ash procedures were also used for WDXRF,

EDXRF, and DCAES (see list below) to concentrate the

trace elements and thereby increase sensitivities. 

Techniques that require analysis of coal ash were used

as described in the following papers in this volume:

Author Procedure

Skeen and others ..... Semiquantitative DCAES

Evans and others ..... WDXRF

EDXRF

Doughten................. ICAP-AES, inductively coupled

argon plasma-atomic emission

spectrometry

FAAS, flame atomic absorption spectrometry

GFAAS, graphite furnace atomic

absorption spectrometry

Briggs ...................... ICAP-AES

Meier ....................... ICAP-MS, inductively coupled argon

plasma-mass spectrometry

All samples were ashed at 525°C to limit volatilization of

lead, cadmium, and other moderately volatile trace elements. Ash yields were determined on the same splits used

for the analyses and were used to calculate data as if determined on a whole-coal basis. The 525°C ash yields, which

are not directly comparable to those determined by ASTM

(American Society for Testing and Materials, 1996) ash procedures (750°C) but are generally similar, can be used to

recalculate back to an ash basis if desired. 

DISCUSSION OF RESULTS

Direct comparison of results presented in previous

papers in this volume is difficult because data are presented

in three different forms depending on the analytical technique used and the material analyzed. Concentrations are

reported on an ash basis for some procedures, on a wholecoal basis for some procedures, and on an oxide basis of the

ash for major elements determined by WDXRF and

DCAES. To facilitate a direct comparison of the data, the

ash data have been recalculated to whole-coal values and

converted to an element basis for those elements reported on

an oxide basis. The entire recalculated data set for all splits

can be found in appendix 1. The number of significant figures given in the original papers has been maintained in the

converted values.

A careful examination of appendix 1 shows that analytical procedures can be classified into two categories: highly

precise (HP) procedures shown in bold, which generally

have a relative standard deviation of less than 5 percent, and

procedures that are less precise (LP). The precision was calculated by determining the percent of difference between

the three individual data points and their mean for each sample-element pair. Using the accuracy guidelines discussed

later in this paper, each test for each element was given a

rating of good, usable, or poor precision. Comparisons of

the different ratings for all elements determined by each

technique were made. Finally, the techniques were divided

into the two precision groups (LP and HP) based on which

rating they received most frequently. In this study, the two

DCAES procedures (ash and whole coal) and the X-ray

whole-coal procedures were classified as LP procedures;

INAA, ICAP-AES, ICAP-MS, CVAAS, HGAAS, FAAS,

GFAAS, and the other X-ray procedures were classified as

HP procedures. It should be noted that no procedures had

the same precision for all elements in all samples. For the

designated HP techniques, most determinations were of

high precision, but as expected, determinations near the

detection limit for some samples had poorer precision. LP

procedures generally had lower precision for all samples

and elements.

Statistical approaches are useful for large data sets;

however, often they do not provide the detail that is useful in

evaluating individual problems in the data. Even though the

individual samples were analyzed only in triplicate, the

complete data set requires 18 pages (appendix 1). A summary of the data is given in tables 1 and 2. Table 1 presents

the method averages of the major rock-forming-element

data determined on each of the three splits of the eight

Argonne Premium Coal samples. Table 2 is a similar table

for the trace-element data. 

Statistical analysis of the data in appendix 1 is given in

appendix 2. These data include the number of samples for

which values were determined, the arithmetic mean (mean),

the standard deviation, the relative standard deviation, the
COMPILATION OF MULTITECHNIQUE DETERMINATIONS 63

Table 1. Average concentrations of major elements in weight percent based on triplicate analyses. 

[Values in brackets are averages of two analyses, and numbers in parentheses are based on only one analysis. Data from high-precision techniques are in

bold except outliers. An * indicates that the analysis was done in Denver. Complete data set is given in appendix 1. Material analyzed: (A) = ash, (C) = whole

coal. —, no data]

Element and technique

Argonne Premium Coal sample

UF PC-1 WY PC-2 IL PC-3 PITT PC-4 POC PC-5 UT PC-6 WV PC-7 ND PC-8

Si

 ICAP-AES(A)* .................... 2.6 1.0 2.9 1.8 0.75 0.91 5.0 0.67

 WDXRF(A) .......................... [2.67] [1.24] [3.04] [1.96] [.804] (.893) (4.90) (.768)

 DCAES(A) ............................ 3.1 1.4 3.6 2.7 .95 .86 5.2 .60

 DCAES(C) ............................ 3 .77 3 2 .88 — — —

Al

 WDXRF(A) .......................... [1.54] [.672] [1.21] [.981] [.548] (.370) (3.17) (.45)

 ICAP-AES(A) ...................... 1.60 .699 1.25 .997 .549 [.347] 3.15 .400 

 ICAP-AES(A)* .................... 1.6 .66 1.3 .96 .57 .38 3.2 .40

 DCAES(A) ............................ 2.4 .53 2.0 2.1 .71 .32 3.9 .23

 DCAES(C) ............................ 2 .48 2 2 .85 — — —

Fe

 INAA(C) ............................... 1.78 .366 2.67 1.35 .509 .317 .397 .547

 WDXRF(A) .......................... [1.93] [.33] [2.70] [1.44] [.521] (.29) (.37) (.45)

 ICAP-AES(A) ...................... 1.86 .367 2.72 1.32 .507 [.282] .385 .472

 ICAP-AES(A)* .................... 1.7 .34 2.4 1.2 .50 .30 .39 .46

 DCAES(A) ............................ 1.6 .27 2.4 1.9 .50 .24 .40 .37

 DCAES(C) ............................ 2 .29 2 1 .69 — — —

Mg

 WDXRF(A) .......................... [.079] [.26] [.09] [.03] [.067] (.048) (.08) (.42)

 ICAP-AES(A) ...................... .082 .239 .077 .038 .0548 [.030] .094 .398

 ICAP-AES(A)* .................... .078 .21 .073 .033 .0554 .030 .085 .351

 DCAES(A) ............................ .15 .37 .12 .073 .11 .041 .097 .51

 DCAES(C) ............................ .099 .20 .098 .048 .077 — — —

Ca

 WDXRF(A) .......................... [.40] [1.12] [.90] [.20] [.443] (.401) (.06) (1.54)

 ICAP-AES(A) ...................... .445 1.19 .960 .206 .456 [.409] .058 1.54

 ICAP-AES(A)* .................... .40 1.0 .92 .19 .45 [.43] .058 1.4

 DCAES(A) ............................ .64 1.2 1.6 .41 .58 .29 .078 1.3

 DCAES(C) ............................ .58 1 2 .29 .80 — — —

Na

 INAA(C) ............................... .0341 .115 .102 .0343 .0782 .146 .0388 .529

 ICAP-AES(A) ...................... .032 .119 .097 .032 .0826 [.126] .034 .466

 ICAP-AES(A)* .................... .034 .12 .11 .034 .0826 .13 .036 .493

 WDXRF(A) .......................... [.03] [.092] (.13) [.03] [.071] (.13) (.05) (.50)

 DCAES(A) ............................ .045 .13 .15 .036 .13 .072 .036 (.25)

K

 INAA(C) ............................... .269 .0292 .195 .110 .029 [.022] .505 [.029]

 WDXRF(A) .......................... [.27] [.03] [.20] [.11] [.03] (.02) (.46) (.03)

 ICAP-AES(A) ...................... .283 .028 .194 .110 .028 [.014] .495 .014

 ICAP-AES(A)* .................... .29 .033 .22 .11 .035 .028 .49 .037

 DCAES(A) ............................ .30 .033 .26 .13 .036 .017 .36 .037

Ti

 WDXRF(A) .......................... 0.080 [0.051] [0.07] [0.059] [0.040] (0.02) (0.24) (0.02) 

 ICAP-AES(A) ...................... .079 .056 .070 .056 .038 [.023] .260 .020

 ICAP-AES(A)* .................... .075 .051 .069 .050 .040 .023 .23 .019

 DCAES(A) ............................ .053 .036 .066 .057 .028 .019 .18 .018

 DCAES(C) ............................ .10 .044 .092 .091 .082 — — —

P

 WDXRF(A) .......................... [.006] [.03] [.004] [.01] [.002] (.001) (.007) (.02)

 ICAP-AES(A) ...................... .0079 .025 .0059 .011 .0022 [.00094] .0084 .012

 ICAP-AES(A)* .................... .0059 .022 .004 .0080 [.0023] .0007 .008 .012

 WDXRF(C) ........................... — .03 — .009 — — — .02

 DCAES(A) ............................ — .026 — — — (.00074) (.017) .011

Mn

 WDXRF(A) .......................... ——————— (.007) 

 ICAP-AES(A) ...................... .0041 .0020 .0076 .0018 .0016 [.00041] .0015 .0080

 ICAP-AES(A)* .................... .0044 .0020 .0087 .0021 .0018 .00042 .0014 .0082

 DCAES(A) ............................ .0055 .0033 .0011 .0036 .0024 .00061 .0020 .010

 DCAES(C) ............................ .0053 .0013 .0016 .0020 .0019 — — —
64 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 2. Average concentrations of trace elements in parts per million based on triplicate analyses. 

[Bracketed values are averages of two analyses, and numbers in parentheses are based on only one analysis. Data from high-precision techniques are in bold

except outliers. An * indicates that the analysis was done in Denver. Complete data set is given in appendix 1. Material analyzed: (A) = ash, (C) = whole

coal. —, no data] 

Element and technique

Argonne Premium Coal sample

UF PC-1 WY PC-2 IL PC-3 PITT PC-4 POC PC-5 UT PC-6 WV PC-7 ND PC-8

Li

FAAS(A)................................ 15 4.1 7.8 8.6 5.8 5.1 29 2.7

ICAP-AES(A)*..................... 15 3.9 7.7 8.9 5.5 5.5 27 2.7

Be

ICAP-AES(A)....................... 1.5 .25 .76 .77 .80 [.13] 1.9 [.18]

ICAP-AES(A)*..................... 1.5 .3 .6 .7 .80 .1 2.1 .2

DCAES(A)............................. 1.4 .14 .97 1.2 .67 .20 3.0 .28

B

ICAP-AES(A)*..................... 38 96 160 48 13 130 56 79

DCAES(A)............................. 30 70 120 51 17 — 57 67

Sc

INAA(C) ............................... 4.06 1.68 2.59 2.57 1.79 .813 7.62 .846

ICAP-AES(A)*..................... 3.9 1.6 2.7 2.5 1.8 .75 7.4 .8

DCAES(A)............................. 2.1 1.3 2.6 1.9 1.3 .69 6.4 .90

V

ICAP-AES(A)....................... 26 14 32 15 11 [4.0] 44 3.5

ICAP-AES(A)*..................... 27 14 37 17 12 4.5 43 3.9

DCAES(A)............................. 16 9.0 24 13 7.1 3.7 32 3.6

DCAES(C)............................. 41 14 52 24 18 — — —

Cr

INAA(C) ............................... 20.3 6.1 33.1 14.8 9.1 5.30 35.8 2.24

EDXRF(A)............................ 26.0 [8.2] 43.2 17.9 12.3 — 45.9 2.6

ICAP-AES(A)....................... 20 6.2 31 14 9.2 [4.8] 40 2.4

ICAP-AES(A)*..................... 22 6.4 36 16 9.7 5.2 39 2.3

EDXRF(C)............................. 19 [4] 35 8 5 — 49 —

DCAES(A)............................. 19 5.7 38 19 8.8 4.8 39 2.4

DCAES(C)............................. 32 7 52 24 16 — — —

Co

INAA(C) ............................... 5.33 1.68 4.31 2.62 4.07 1.00 7.74 .778

FAAS(A)................................ 5.0 1.6 4.3 2.4 3.8 [.83] 8.1 —

ICAP-AES(A)*..................... 5.3 1.7 4.4 2.6 4.0 .94 7.5 .9

DCAES(A)............................. 3.5 1.3 3.7 2.6 2.6 .64 6.3 .55 

DCAES(C)............................. 5 — — — 5 — ——

Ni

INAA(C) ............................... 14.5 4.9 21.0 [10.3] 8.6 [3.4] 15.4 —

EDXRF(A)............................ 14 3.9 18 9.3 7.58 — 17 1.9

ICAP-AES(A)....................... 14 4.9 18 8.5 6.7 [3.3] 16 1.3

ICAP-AES(A)*..................... 17 4.8 [19] 9.1 7.4 3.5 16 1.4

EDXRF(C)............................. 23 8 32 14 11 5 18 6

DCAES(A)............................. 14 5.2 22 13 6.5 4.0 21 1.8

DCAES(C)............................. 25 — 33 12 [11] — — —

Cu

EDXRF(A)............................ 20.4 12.9 9.6 6.2 12.5 — 23.6 3.3

ICAP-AES(A)....................... 19 12 10 5.5 12 [3.8] 19 4.7

ICAP-AES(A)*..................... 19 14 11 5.8 16 4.2 21 [4.6]

EDXRF(C)............................. 18 17 14 10 17 8 31 9

DCAES(A)............................. 17 13 11 6.5 19 2.9 16 4.9

DCAES(C)............................. 18 7 9 6 19 — — —

Zn

INAA(C) ............................... 19.7 11.3 220 9.1 6.4 6.35 13.5 5.69

EDXRF(A)............................ 20.5 10.6 107 8.4 4.8 — 12 5.4

ICAP-AES(A)....................... 19 10 180 7.8 4.0 [6.2] 13 4.6

ICAP-AES(A)*..................... 19 12 190 [8.1] 5.3 4.8 11 4.8

EDXRF(C)............................. 33 25 140 15 14 — 10 5

DCAES(C)............................. 33 — 280 27 — — — —
COMPILATION OF MULTITECHNIQUE DETERMINATIONS 65

Table 2. Average concentrations of trace elements in parts per million based on triplicate analyses—Continued. 

Element and technique

Argonne Premium Coal sample

UF PC-1 WY PC-2 IL PC-3 PITT PC-4 POC PC-5 UT PC-6 WV PC-7 ND PC-8

Ga

ICAP-AES(A)* .................... 5.34 1.91 3.57 3.28 1.80 1.00 9.39 1.16

DCAES(A)............................ 6.2 2.4 4.7 4.7 2.3 1.2 12 1.7

DCAES(C) ............................ 10 3 7 5 4 — ——

Ge

ICAP-MS(A)* ....................... 4.35 0.36 8.40 1.25 0.29 0.23 1.7 0.37

DCAES(A) ............................. 3.6 — 8.9 1.2 .46 — [1.1] —

DCAES(C) ............................. 4 — 9 (3) — — — —

As

INAA(C) ................................ 17.1 3.6 4.7 8.42 10.3 .48 6.2 2.63

ICAP-MS(A)* ....................... 16.1 2.4 3.8 7.6 9.9 (.33) 6.7 (1.6)

DCAES(A) ............................. 30 — — 17 15 — — —

Se

INAA(C) ................................ 1.92 1.56 4.29 1.5 2.5 1.08 5.4 .58

HGAAS(C) ............................ 1.9 2.4 4.1 1.7 3.0 1.3 5.8 .60

Rb

INAA(C) ................................ 19.5 — 16 7.7 — .98 29.7 [.93]

ICAP-MS(A)* ....................... 22.0 1.80 15.7 8.12 2.11 1.06 36.3 1.41

EDXRF(A)............................. 21.2 3.5 15 9.1 2.3 — 43.6 —

EDXRF(C) ............................. 21 13 20 8 5 3 42 4

Sr

INAA(C) ................................ 49 252 39 61 105 70 60 597

EDXRF(A)............................. 60 260 29.9 68 110 — 78.0 640

ICAP-AES(A) ....................... 59 150 29 64 85 [60] 49 500

ICAP-AES(A)* ..................... 58 260 31 64 110 60 62 490

EDXRF(C) ............................. 62 294 33 63 85 63 86 780

DCAES(A) ............................. 63 220 40 91 110 89 70 630

Y

EDXRF(A)............................. 10 3.6 4.1 4.9 6.89 — 21.2 —

ICAP-AES(A) ....................... 9.3 3.8 4.2 4.3 6.2 2.0 11 [1.8]

ICAP-AES(A)* ..................... 8.1 3.6 4.0 4.0 5.8 2.0 12 2.2

EDXRF(C) ............................. — — — — — (2) 19 —

DCAES(A) ............................. 4.7 3.0 4.7 3.1 4.6 1.8 9.1 2.4

Zr

ICAP-AES(A)* ..................... 24 19 23 18 16 17 69 12

EDXRF(A)............................. 27.3 22.7 22.3 20.5 16.9 — 80.5 6.5

EDXRF(C) ............................. 23 19 23 17 10 18 103 18

DCAES(A) ............................. 11 17 17 12 12 11 34 13

DCAES(C) ............................. 33 — 21 24 30 — — —

Nb

ICAP-MS(A)* ....................... 2.4 1.4 2.2 1.7 1.1 .57 6.1 .79

EDXRF(A)............................. 2.5 1.0 [2.1] 1.9 .85 — 8.3 —

EDXRF(C) ............................. —————— [13] —

DCAES(A) ............................. 1.7 1.4 2.5 1.8 1.1 .51 3.6 .58

Mo

ICAP-MS(A)* ....................... 2.50 .52 6.23 .74 2.67 .42 1.3 .42

DCAES(A) ............................. 1.5 .67 5.2 .80 2.2 .48 1.4 .81

Ag

ICAP-MS(A)* ....................... .46 .23 .62 .31 .23 .15 1.2 .16

DCAES(A) ............................. .21 .067 .367 .088 .099 .47 .45 —

Cd

ICAP-MS(A)* ....................... .17 .12 .79 .11 .072 .077 .055 .040

GFAAS(A) ............................. .071 .094 .61 .061 .078 [.060] .078 .046

Sn

ICAP-MS(A)* ....................... .96 .32 .72 .57 .37 .16 1.7 .38

DCAES(A) ............................. 1.67 .86 2.4 1.3 72 .37 1.9 (1.23)
66 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 2. Average concentrations of trace elements in parts per million based on triplicate analyses—Continued. 

Element and technique

Argonne Premium Coal sample

UF PC-1 WY PC-2 IL PC-3 PITT PC-4 POC PC-5 UT PC-6 WV PC-7 ND PC-8

Sb

INAA(C)................................. .531 .191 .877 .233 .539 .107 .521 .153

ICAP-MS(A)*........................ .49 .16 .79 .20 .27 .089 .56 .16

Cs

INAA(C)................................. 1.52 .191 .877 .70 .262 .130 1.86 .086

ICAP-MS(A)*........................ 1.89 .19 1.4 .80 .22 .14 2.33 .10

Ba

INAA(C)................................. 61 310 94 47 198 36 133 680

EDXRF(A) ............................. 52 270 74.5 35.7 180 — 110 460

ICAP-AES(A) ........................ 55 15 81 41 16 31 120 420

ICAP-AES(A)* ...................... 56 290 82 39 210 35 120 530

EDXRF(C) .............................. 60 410 121 30 140 29 210 1030

DCAES(A).............................. 41 320 60 38 210 36 130 580

DCAES(C) .............................. 81 250 120 66 450 — — —

La

INAA(C)................................. 10.1 5.35 6.10 6.15 6.76 3.31 21.5 2.82

ICAP-MS(A)*........................ 7.7 4.0 5.9 4.6 5.67 2.5 17 1.9

EDXRF(A) ............................. 8.2 — — [4.4] 2.2 — 17 —

EDXRF(C) .............................. 16 6 15 9 5 10 16 8

DCAES(A).............................. 6.9 6.1 9.3 5.8 7.2 2.9 14 3.7

Ce

INAA(C)................................. 18.3 9.4 12.6 11.3 11.6 4.81 35.8 4.45

ICAP-MS(A)*........................ 17.6 8.0 12 10.3 11.3 4.7 37.1 4.1

EDXRF(A) ............................. 17.0 [5.2] 7.2 9.0 7.6 — 29.9 —

EDXRF(C) .............................. 40 25 40 17 10 15 55 19

DCAES(A).............................. (10) 9 (28) — 12 6.9 26 —

Pr

ICAP-MS(A).......................... 1.93 .926 1.3 1.12 1.29 .546 4.06 .43

DCAES(A).............................. — — — — — .42 [1.87] —

Nd

INAA(C)................................. (8.0) — — — — 2.0 11.9 2.3 

ICAP-MS(A)*........................ 7.5 3.6 5.2 4.3 5.1 2.1 15 1.5

DCAES(A).............................. 8 — (6.5) 3.9 6.0 (2.9) 19 —

Sm

INAA(C)................................. 1.97 .978 1.20 1.10 1.22 .508 3.52 .409

ICAP-MS(A)*........................ 1.55 .71 1.0 .83 .995 .37 2.80 .26

DCAES(A).............................. ———— .76 .37 [1.7] (.47)

Eu

INAA(C)................................. .398 .198 .226 .214 .234 .099 .674 .081

ICAP-MS(A)*........................ .34 .17 .20 .17 .21 .084 .61 .054

DCAES(A).............................. ————— (.11) .61 —

Tb

INAA(C)................................. .262 .120 .138 .132 .167 .058 .400 .056

ICAP-MS(A)*........................ .23 .10 .14 .11 .16 .055 .40 .055

Yb

INAA(C)................................. .88 .42 .52 .470 .555 .204 1.61 .287

ICAP-MS(A)*........................ .81 .37 .52 .43 .572 .20 1.5 .23

DCAES(A).............................. .84 .29 .61 .54 .45 .21 1.5 .20

Hf

INAA(C)................................. .66 .601 .55 .50 .438 .478 1.83 .341

ICAP-MS(A)*........................ .85 .68 .76 .61 .56 .56 2.3 .42

Ta

INAA(C)................................. .219 .146 .191 .166 .116 .048 .641 .092

ICAP-MS(A)*........................ .20 .12 .18 .13 .11 .046 .583 —
COMPILATION OF MULTITECHNIQUE DETERMINATIONS 67

geometric mean, the deviation of the arithmetic and geometric means, and an analysis of the kurtosis and skewness

for the HP techniques excluding outliers (values with only

one significant figure and HP values excluded because of

the 40 percent rule discussed in the next paragraph). A similar analysis for all values, including LP values, outlier values, and other excluded values, is also given in appendix 2.

Another approach to analyzing the data is to define the

agreement between techniques in a useful, nonstatistical

manner and then discuss individual cases of disagreement.

In a practical sense, for major elements (elements with concentrations generally greater than 0.1 percent; table 1),

procedures are said to have “good accuracy” if the standard deviation of the individual determinations for a given

sample determined by a given technique is ±5 percent of the

mean of all of the HP procedures and does not disagree by

more than ±0.5 pecent absolute. For trace elements (table 2)

“good agreement” is defined as ±10 percent of the mean.

“Usable agreement” is four times the uncertainty of “good

agreement” or ±20 percent for the majors and ±40 percent

for the traces. Excluded from the agreement analysis were

values of only one significant figure. If more than two tests

were used, a mean value for a given technique differing by

more than 40 percent from the mean of the remaining values

was reason for excluding a given technique. This is the “40

percent rule.” The excluded technique was said to have poor

agreement for elements in those samples. In addition, the

Grubbs test (Taylor, 1987) was made for all suspected HP

outliers, using the mean and standard deviation for all HP

techniques. Outliers are reported in table 3 under exceptions. They were excluded from the determination of agreement except for cases where the outlier was the only value

for an element determined by a given technique. Figure 1

summarizes the decisions required to determine the agreement.

Trace-element criteria were applied to those samples

containing elements that are traditionally considered major

or minor elements (table 1), but whose mean concentration

for HP techniques was less than 0.1 percent. This included

phosphorus and manganese for all samples and magnesium,

sodium, potassium, and titanium (see table 3) for four or

more samples. It should be noted that the ±5 percent criterion for “good agreement” is better than expected for some

HP techniques for some samples as concentrations

approach the detection limit. For example, counting errors

of as high as 28 percent are reported for potassium by INAA

(see paper by Palmer, this volume). The criterion of 20 percent required for “usable agreement” is much smaller than

the inherent precision for many of the LP techniques. Skeen

and others, in this volume, report possible errors of +50 percent or -33 percent because of the nature of the standards

for each of the elements. It is not surprising, therefore, that

not all HP techniques have “good agreement” for all samples and that most LP techniques have “poor agreement” for

most samples. Most of these disagreements were within ±50

percent of the HP mean concentrations, and scatter in intertechnique comparison plots simply demonstrates the poorer

precision of the LP techniques. A complete discussion of

the precision of all values in this study is beyond the scope

of this paper, but an indication of the precision can be

obtained by examining appendix 1 and by the relative standard deviation given in appendix 2. 

Table 2. Average concentrations of trace elements in parts per million based on triplicate analyses—Continued. 

Element and technique

Argonne Premium Coal sample

UF PC-1 WY PC-2 IL PC-3 PITT PC-4 POC PC-5 UT PC-6 WV PC-7 ND PC-8

W

INAA(C) ................................ 1.06 .38 1.52 .78 .84 .42 1.68 .35

ICAP-MS(A)* ....................... 1.2 .46 1.62 .86 1.1 .51 [1.6] .36

Pb

GFAAS(A) ............................. 7.4 2.9 6.5 2.9 2.4 [1.6] 12 1.5

ICAP-MS(A)* ....................... 7.6 1.6 8.5 3.8 1.7 1.5 12 1.6

DCAES(A) ............................. 10 3.4 14 7.3 11 1.9 16 2.6

DCAES(C) ............................. 8 — 8 4 5 — ——

Bi

ICAP-MS(A*) ....................... .12 .053 [.088] .12 .052 .035 .23 —

DCAES(A) ............................. — — — [1.8] — — — —

Th

INAA(C) ................................ 2.26 1.71 1.96 1.48 1.16 .615 6.41 1.07

ICAP-AES(A)* ..................... 2.7 1.4 2.2 1.6 1.2 .58 6.4 .7

U

INAA(C) ................................ .83 .54 4.27 .39 .51 .74 1.64 [.49]

ICAP-MS(A)* ....................... 1.2 .63 6.46 .57 .631 .852 2.16 .45
68 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 3. Agreement between techniques for major elements using data from table 1 and criteria described in text. 

[The following abbreviations were used under Exceptions: Samples: 1 = UF PC-1; 2 = WY PC-2; 3 = IL PC-3; 4 = PITT PC-4; 5 = POC PC-5; 6 =

UT PC-6; 7 = WV PC-7; 8 = ND PC-8. Those that differ from the overall agreement are followed by g = good agreement; u = usable agreement; p =

poor agreement; or x = no values or only upper limits found. High-precision (HP) techniques are in bold for consistency with other tables. HP values

not used to calculate the mean are identified with an s for values with only one significant figure, f for values rejected because of the 40 percent rule

(see text), or an o for single values rejected using the Grubbs outlier test (Taylor, 1987). All values including outliers were used to determine overall

agreement. The mean of these values was used for comparison in evaluating low-precision values. Sample numbers in parentheses are samples where

only single determinations are available. Agreement calculated using trace-element criteria because of low concentration in sample was designated

with a t. Material analyzed: (A) = ash; (C) = whole coal; * = done in Denver] 

Element

Exceptions

to major

 elements 

HP

techniques

Overall

agreement Exceptions LPtechniques 

Overall

agreement Exceptions

Si................................. ICAP-AES(A)* Good 2u,3o,8= DCAES(A) Usable 3,6,7g;2,4,5p

 WDXRF(A) Good 2,4,5u,(8)ou DCAES(C) Poor 3sg;1s,4s,5u;6–8x

Al ................................ WDXRF(A) Good (8)ou DCAES(A) Poor 6u

 ICAP-AES(A) Good (6)u DCAES(C) Poor 1s,3s,4s;6–8x

ICAP-AES(A)* Good 3o,4o,5o

Fe ................................ INAA(C) Good 6,8u DCAES(A) Usable 5g;2,4,8p

 WDXRF(A) Good 1,2,4,(8)u DCAES(C) Usable 3s,4s,5p;6–8x;1s

 ICAP-AES(A) Good 6u 

ICAP-AES(A)* Good 1,3,4,8u 

Mg.......... 1,3–7t WDXRF(A) Usable 1g;(6)p;3s,4s,(7)s

 ICAP-AES(A) Good DCAES(A) Poor 7g;6u

ICAP-AES(A)* Good 2,8u DCAES(C) Usable 6–8x

Ca........... 7t WDXRF(A) Good (7)s DCAES(A) Poor 2,7,8u

 ICAP-AES(A) Good 1,2u DCAES(C) Poor 2su;6–8x;3s

ICAP-AES(A)* Good 2,4u;6o

Na........... 1,4,5,7t INAA(C) Good 6–8u DCAES(A) Usable 4,7g;3,5,6,(8)p

 ICAP-AES(A) Good 3,5,6,8u 

ICAP-AES(A)* Good 2u

 WDXRF(A) Usable (8)g;(7)sp;1s,4s 

K ............ 2,5,6,8t INAA(C) Good 6,8u DCAES(A) Usable 3,7p

 WDXRF(A) Good (6)su;2s,5s,(8)s 

ICAP-AES(A) Usable 1,3,4,7g;8fp 

ICAP-AES(A)* Good 2,3,5,8u 

Ti............ 1–6,8t WDXRF(A) Good (6)su:3s,(8)s DCAES(A) Usable 3,4,8g;7p

 ICAP-AES(A) Good DCAES(C) Usable 4,5p;6–8x

ICAP-AES(A)* Good

P............. 1–8t WDXRF(A) Usable 4sg;(8)sp;1s,2s,

3s,5s;(6)s,(7)s

 ICAP-AES(A) Good 1,4,6u;3,7= WDXRF(C) Poor 4sg;2su;8sp;1,3,5–7x

ICAP-AES(A)* Good 1,4;3s,6su;7s DCAES(A) Poor 8g;7p;1,3–5x

Mn.......... 1–8t WDXRF(A) Usable 1–7x,8sg DCAES(A) Usable 2,3,4,6p

ICAP-AES(A) Good DCAES(C) Usable 4g;3p;6–8x 

ICAP-AES(A)* Good
COMPILATION OF MULTITECHNIQUE DETERMINATIONS 69

Figure 1. Decision tree for determination of agreement between techniques for each element.

A summary of the agreement for major elements is

given in table 3. Data for elements by specific techniques

were classified as in “overall good agreement” with the

mean of the HP procedures if at least half of the individual

samples were in “good agreement” using the previously

mentioned criteria, and no samples had “poor agreement.” If

half or more of the samples determined were in “good” or

“usable agreement” and the technique was not classified as

in “good agreement,” the element had “overall usable agreement.” All others had “overall poor agreement” except

where the technique was the only HP technique. In this

case, agreement could not be determined. The mean of the

samples for this sole HP technique was used to assess the

agreement of the LP techniques, and no accuracy designation was given. All HP techniques listed in table 3 were in

“overall good agreement” except for sodium, magnesium,

manganese, and phosphorus determined by WDXRF on the

ash, and potassium determined by ICAP-AES in Reston.

These were classified as having “overall usable agreement.”

In contrast, all LP techniques had “overall poor” or “overall

usable agreement.” 

Table 4 summarizes the agreement of trace elements.

All agreements were evaluated using trace-element criteria

discussed previously and summary classifications similar to

those in table 3. HP procedures generally had “good agreement” and none had “poor agreement,” whereas LP procedures generally had “usable” or “poor agreement,” with

only an occasional “good agreement.” 

Most of the data fall within expected precision limits,

but barium is an example of a case where determining an

element by more than one technique can make a significant

difference. Agreement between techniques can be graphically represented by plotting the concentrations of all

elements determined by one technique versus all corresponding concentrations by a second technique and comparing these points to a theoretical line with zero intercept

and a slope of 1. Figure 2, for example, shows the comparison of INAA and ICAP-AES data from table 2 for all elements that the two techniques have in common. There is
70 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Table 4. Agreement between techniques for trace elements using data from table 2 and criteria described in text. 

[The following abbreviations were used under Exceptions: Samples: 1 = UF PC-1; 2 = WY PC-2; 3 = IL PC-3; 4 = PITT PC-4; 5 = POC PC5; 6 = UT PC-6; 7 = WV PC-7; 8 = ND PC-8. Those that differ from the overall agreement are followed by g = good agreement; u = usable

agreement; p = poor agreement; or x = no values or only upper limits found. High-precision (HP) techniques are in bold for consistency with

other tables. HP values not used to calculate the mean are identified with an s for values with only one significant figure, an f for values

rejected because of the 40 percent rule (see text), or an o for single values rejected using the Grubbs outlier test (Taylor, 1987). All values

including outliers were used to determine overall agreement. Equal sign “=” indicates there are no other high-precision values; italicized

“good” agreements indicate that the only high-precision techniques used in determining the accuracy were modifications of the same tests,

ICAP-AES(A) done in Reston and Denver. The mean of these values was used for comparison in evaluating low-precision values. Sample

numbers in parentheses are samples where only single determinations are available. Material analyzed: (A) = ash; (C) = whole coal; * = done

in Denver. —, no agreement could be calculated] 

Element HP

techniques

Overall

agreement Exceptions LPtechniques 

Overall

agreement Exceptions

Li ................ FAAS(A) Good

ICAP-AES(A)* Good

Be ............... ICAP-AES(A) Good 2–4,6,8= DCAES(A) Poor 1g;3,5u

ICAP-AES(A)* Good 2s,3s,6su;4s,8s

B ................. ICAP-AES(A)* — 1–8= DCAES(A) Usable 4,7g;6x

Sc................ INAA(C) Good 8= DCAES(A) Usable 3,8g;1p

ICAP-AES(A)* Good 8s

V................. ICAP-AES(A) Good DCAES(A) Usable 8g

ICAP-AES(A)* Good DCAES(C) Poor 2g;6–8x

Cr................ INAA(C) Good 7u EDXRF(C) Usable 3g;4s,5sp;6,8x;

2s

 EDXRF(A) Usable 8g;6x;2o DCAES(A) Good 1,2,4,5u

 ICAP-AES(A) Good 3,4u DCAES(C) Poor 2sg;6–8x

ICAP-AES(A)* Good

Co ............... INAA(C) Good 8= DCAES(A) Usable 4g

 FAAS(A) Good 6u;8x DCAES(C) Usable 1sg;2–4,6–8x;

5s

ICAP-AES(A)* Good 8su

Ni................ INAA(C) Good 4,5u;8x EDXRF(C) Poor 7u;2s,6s,8s

 EDXRF(A) Good 2,8u;6x DCAES(A) Usable 1g;4p

 ICAP-AES(A) Good 5,8u DCAES(C) Poor 4u;2,6–8x

ICAP-AES(A)* Good 1,3ou

Cu ............... EDXRF(A) Good 7,8u;6x EDXRF(C) Usable 1g;4,6s,7,8sp

 ICAP-AES(A) Good 5,7,8u DCAES(A) Usable 2,3g;5p

ICAP-AES(A)* Usable 1–4,6,7g;8op DCAES(C) Usable 1,4g;2,5p;6–8x

Zn ............... INAA(C) Good 3,5,8u EDXRF(C) Poor 8sg;3,7u;6x EDXRF(A) Usable 1,2,4,5,7,8g;3fp,6x ICAP-AES(A) Good 5,8u DCAES(C) Poor 2,5–8x

ICAP-AES(A)* Good 4o,6u

Ga ............... ICAP-AES(A)* — 1–8= DCAES(A) Usable 4,8p

 DCAES(C) Poor 6–8x;2s,3s,4s,

5s

Ge ............... ICAP-MS(A)* — 1–8= DCAES(A) Usable 3,4g;5p;2,6,8x

 DCAES(C) Usable 1s,3sg;(4)sp;

2,5–8x

As ............... INAA(C) Good 2,3,6,8u DCAES(A) Poor 2,3,6–8x

ICAP-MS(A)* Usable 1,3-5,7g;8o

Se................ INAA(C) Good 2u

HGAAS(C)* Good 2u,7o

Rb ............... INAA(C) Good 7,8u;2,5x EDXRF(C) Usable 1,4sg;2,5s,6s,

8sp

 ICAP-MS(A)* Good 2,8u

EDXRF(A) Good 2,7u;6,8x 
COMPILATION OF MULTITECHNIQUE DETERMINATIONS 71

Table 4. Agreement between techniques for trace elements using data from table 2 and criteria described in text—

Continued. 

Element HP

techniques

Overall

agreement Exceptions LPtechniques 

Overall

agreement Exceptions

Sr................. INAA(A) Good 1,3,6u EDXRF(C) Good 2,5,7,8u

 EDXRF(A) Good 7,8u;6x DCAES(A) Usable 1,5g;4,6p

 ICAP-AES(A) Usable 1,4,6g;2fp

ICAP-AES(A)* Good 8u

Y ................. EDXRF(A) Usable 1–3,5g;6,8x;7fp EDXRF(C) Usable (6)sg,7p;1–5, 

8x

 ICAP-AES(A) Good 8u DCAES(A) Usable 1p

ICAP-AES(A)* Good 1u

Zr ............... ICAP-AES(A)* Good 8u,6= EDXRF(C) Usable 2,3,6g;8p

EDXRF(A) Good 8u;6x DCAES(A) Usable 1,7,8p DCAES(C) Usable 3g;5p;2,6–8x

Nb ............... ICAP-MS(A)* Good 2,7u;6,8= EDXRF(C) Poor 1–6,8x

EDXRF(A) Usable 1,3,4g;6,8x DCAES(A) Usable 4,6g;7p

Mo............... ICAP-MS(A)* — 1–8= DCAES(A) Usable 4g;1,8p

Ag ............... ICAP-MS(A)* — 1–8= DCAES(A) Poor 8x

Cd ............... ICAP-MS(A)* Usable 5,6,8g;1p

GFAAS(A) Usable 5,8g

Sn................ ICAP-MS(A)* — 1–8= DCAES(A) Poor 7g

Sb................ INAA(C) Good 5u

ICAP-MS(A)* Good 5u

Cs................ INAA(C) Good 1,3,7u

ICAP-MS(A)* Good 1,3,7u

Ba................ INAA(C) Good 3,4,8u EDXRF(C) Usable 1g;2,3,7,8p EDXRF(A) Good 4,7,8u;6x DCAES(A) Good 1,3,8u ICAP-AES(A) Usable 1,3,4,6,7g;2f,5fp DCAES(C) Poor 2u;6–8x

ICAP-AES(A)* Good

La................ INAA(C) Usable 3,5g EDXRF(C) Poor 2s,5s,7u;4s,6s,

8s

ICAP-MS(A)* Usable 5,3,7g

 EDXRF(A) Usable 1,7g;5fp;2,3,6,8x DCAES(A) Usable 6g;3,8p 

Ce................ INAA(C) Good 2–5u EDXRF(C) Poor 5g

 ICAP-MS(A)* Good 3,5u DCAES(A) Poor 2,5,7u;4,8x

EDXRF(A) Usable 1g;6,8x 

Pr................. ICAP-MS(A)* — 1–8= DCAES(A) Poor 6u;1–5,8x

Nd ............... INAA(C) Usable (1),6g;2–5x DCAES(A) Usable 1s,4g;7p;2,8x

ICAP-MS(A)* Good 8u;2–5=

Sm............... INAA(C) Usable 3g DCAES(A) Poor 5,6u;1–4x

ICAP-MS(A)* Usable 3g

Eu................ INAA(C) Good 4,8u DCAES(A) Usable 6u,7g;1–5,8x

ICAP-MS(A)* Good 4,8u

Tb................ INAA(C) Good

ICAP-MS(A)* Good

Yb ............... INAA(C) Good 8u DCAES(A) Usable 1,6,7g

ICAP-MS(A)* Good 8u

Hf................ INAA(C) Good 1,3,5,7u

ICAP-MS(A)* Good 1,3,5,7u
72 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Figure 2. A comparison of average concentrations (in parts per million) of all elements

determined by both inductively coupled argon plasma-atomic emission spectrometry in Reston,

Va. (ICAP-AES (R)), on the ash and instrumental neutron activation analysis (INAA) on the

whole coal. All data determined on the ash are converted to a whole-coal basis. The diagonal

line is the line of perfect agreement. 

Table 4. Agreement between techniques for trace elements using data from table 2 and criteria described in text—

Continued. 

Element HP

techniques

Overall

agreement Exceptions LPtechniques 

Overall

agreement Exceptions

Ta................. INAA(C) Good 4u;8=

ICAP-MS(A)* Good 4u;8x

W ................. INAA(C) Good 5u

ICAP-MS(A)* Good 5u;7o

Pb................. GFAAS(A) Good 2–5u DCAES(A) Poor 1,6,7u

ICAP-MS(A)* Good 2–5u DCAES(C) Usable 1s,3sg;5sp;2,

6–8x;4s

Bi ................. ICAP-MS(A)* — 1–7=,8x DCAES(A) Poor 1–3,5–8x

Th ................ INAA(C) Good 8=

ICAP-AES(A)* Good 8su

U.................. INAA(C) Usable 2,6,8g

ICAP-MS(A)* Usable 2,6,8g
COMPILATION OF MULTITECHNIQUE DETERMINATIONS 73

relatively little scatter (excellent agreement) in most of the

data; therefore, the few problems with the data are easily

recognizable. The most obvious discrepancy in the data is

that the barium concentration determined by ICAP-AES is

more than an order of magnitude smaller in WY PC-2 and

POC PC-5 than the concentration determined by INAA. 

The data for barium determined by the seven different

techniques are shown in figure 3, plotting barium determined by all techniques versus the mean barium concentration determined by high-precision techniques. Although

there is scatter among data from different techniques,

ICAP-AES (R) data for WY PC-2 and POC PC-5 are

clearly off the correlation line. The disagreement of ICAPAES (R) data with data from all other techniques suggests

that barium is present in a species, probably BaSO4, which

is not dissolved by the Reston ICAP-AES acid dissolution

procedures (see paper by Doughten, this volume). ICAPAES procedures done in Denver use a sinter dissolution

procedure and yield Ba concentrations that agree with the

INAA data (see paper by Briggs, this volume). Both of

these coals contain enough sulfate sulfur (Vorres, 1990) to

account for all barium being BaSO4 in the original coal.

Solubility studies of these coals by Finkelman and others

(1990), however, show that barium in these two samples is

soluble in ammonium acetate and is therefore readily

exchangeable. This suggests that BaSO4 is not in the original samples of WY PC-2 and POC PC-5 but that it is

formed in the ashing process. Clearly, the stronger dissolution procedures (see paper by Briggs, this volume) should

be used. 

Some interesting consequences result from the “agreement” rules. Although zinc determined by EDXRF on the

ash had “good agreement” in six samples, the mean of the

zinc values for IL PC-3 was only slightly greater than onehalf of the zinc values determined by INAA and ICAP-AES

for that sample. This difference led to a classification of

“poor agreement” for zinc in IL PC-3 and an overall “usable

agreement.” Although these results are unusual and can be

treated as outliers, as will be discussed later, they relate to

the overall reliability of a technique. Outliers also led to

usable ratings for copper determined by ICAP-AES (Denver), arsenic determined by ICAP-AES (Denver), yttrium

determined by EDXRF, and barium determined by ICAPAES (Reston). Barium had only “overall usable agreement”

because of the “poor agreement” in WY PC-2 and POC PC5, probably caused by incomplete dissolution. Strontium,

Figure 3. The comparison of mean concentration (in parts per million, ppm) in eight Argonne

Premium Coal samples of barium determined by all high-precision techniques excluding

outliers with the average concentrations of barium determined by all techniques. All plotted

data are determined on, or converted to, a whole-coal basis. The diagonal line is the line of

perfect agreement. The high-precision techniques in the legend are in bold. All techniques are

defined in appendix 1; letters in parentheses have the following meanings: C, determined on

whole coal; A, determined on ash (but converted to a whole-coal basis for this figure); R,

analysis performed on ash by the U.S. Geological Survey (USGS) in Reston, Va.; D, analysis

performed on ash by the USGS in Denver, Colo. Error bars given are the range in the y direction

and the standard deviation of the mean in the x direction.

Mean barium content (ppm) determined by HP techniques

Average barium content (ppm) 

determined by all techniques
74 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

determined by ICAP-AES in Reston, showed trends similar

to those of barium except to a lesser extent. Strontium had

one outlier (“poor”), three “good,” and four “usable” values.

All techniques for cadmium, lanthanum, samarium,

and uranium showed only overall “usable agreement” even

though some samples showed “good agreement” for each of

these elements. In these cases it is difficult to determine

which technique may be in error. For cadmium, samarium,

and uranium, there are only two HP techniques. For years

INAA has been considered an excellent technique for the

rare earth elements and may provide the best data for lanthanum and samarium. EDXRF is generally not considered to

be the best technique for rare earth elements such as lanthanum because of spectral overlaps and values generally

near the detection limits. ICAP-MS should produce good

results for the rare earth elements but does not always agree

well with INAA. This disagreement may be due to incomplete dissolution of some rare-earth-bearing species such as

zircon.

Not surprisingly, EDXRF values for cerium yielded

only “usable agreement” because cerium concentrations

were very near the detection limits for this technique. Other

techniques for cerium showed “good agreement.” However,

chromium determined by EDXRF, well above the detection

limit, also showed only “usable agreement,” whereas all

other techniques showed “good agreement.”

The overall agreement of niobium determined by

EDXRF and neodymium determined by INAA was usable

only because several samples had values at or below the

detection limits. Ge, Ga, Mo, Ag, Sn, Pr, and Bi all had only

one HP technique, so no rating could be determined. Beryllium and vanadium were determined only by ICAP-AES in

both Reston and Denver. The “good agreement” that was

expected for these techniques is printed in italics in table 4

because these techniques are modifications of the same

technique. 

The causes of all of the discrepancies are not known.

Overall, however, the data are generally useful and provide

an excellent base for further study.

DETERMINATION OF 

RECOMMENDED VALUES

Because some elements were determined by only one

high-precision technique, because some element concentrations approached their detection limits, and because some

samples contained interfering elements, recommended

values cannot be reliably calculated for all elements in all

coals. Tables 5 and 6 present recommended and average

values for concentrations determined by high-precision

techniques.

Recommended values were determined by using procedures similar to those used in determining agreement ratings. The mean value was considered a recommended value

if the relative standard deviation of all individual determinations of HP techniques excluding outliers was less than 5

percent for major elements or 10 percent for trace elements

using the criteria discussed earlier, and there were at least

four individual determinations. If a recommended value

could not be determined, the value for the statistical parameter responsible for rejection was boxed in appendix 2, and

an average of all HP techniques was reported in parentheses

Table 5. Recommended or average values for major elements in percentages, determined only by high-precision (HP) techniques using

the criteria described in text. 

[Parentheses indicate that the value is only an average of concentrations determined by the HP techniques and is not a recommended value. Complete data

set is given in appendix 1. Statistical analysis of all values, including errors and criteria for not recommending values, is given in appendix 2. “Excluded values” column indicates that the specified HP techniques were not used in determining the given value. The bracketed numbers with the letters indicate the

samples for which the techniques were excluded and the reason the values were rejected. The following abbreviations were used under “Excluded values”:

1 = UF PC-1; 2 = WY PC-2; 3 = IL PC-3; 4 = PITT PC-4; 5 = POC PC-5; 6 = UT PC-6; 7 = WV PC-7; 8 = ND PC-8; o = determined value was an outlier;

s = only one significant figure in all determined values; f = values rejected because of forty percent rule (see text); and n = no values were determined or all

reported values were upper limits. All techniques referred to under “Excluded values” were determined on the ash] 

UF PC-1 WY PC-2 IL PC-3 PITT PC-4 POC PC-5 UT PC-6 WV PC-7 ND PC-8 No. HP

techniques

Excluded

values

Si ........... 2.63 (1.1) 3.05 1.86 0.76 0.91 5.0 (0.67) 2 WDXRF [8o]

Al........... 1.58 .68 1.24 .99 .552 (.37) 3.16 .400 3 WDXRF [8o]

Fe........... (1.8) (.35) (2.6) (1.33) .51 (.30) .39 (.49) 4

Mg......... .080 (.23) .075 .036 .058 (.033) .090 (.38) 3 WDXRF [3s,4s,7s]

Ca .......... (.42) (1.12) .93 (.197) .452 .41 .058 1.49 3 WDXRF [7s]

Na.......... .033 (.11) (.10) .033 .079 (.135) .0348 (.50) 4 WDXRF [1s,4s,7s]

K............ .28 (.030) (.20) .111 (.031) (.025) .49 (.034) 4 WDXRF [2s,5s,6s,8s]

ICAP-AES [6f,8f]

Ti ........... .078 .053 .070 .055 .039 .023 (.25) .0192 3 WDXRF [3s,6s,8s]

P ............ (.007) .024 (.0059) (.010) .00222 (.00095) (.0083) .012 3 WDXRF [1–3s,5–8s]

ICAP-AES* [3s,6s,7s]

Mn......... .0043 .0020 .0081 .0019 .0017 .000416 .00147 .0081 3 WDXRF [1–8n]
COMPILATION OF MULTITECHNIQUE DETERMINATIONS 75

Table 6. Recommended or average values for trace elements in parts per million, determined only by high-precision (HP) techniques

using the criteria described in text. 

[Parentheses indicate that the value is only an average of concentrations determined by the HP techniques and is not a recommended value. Complete data

set is given in appendix 1. Statistical analysis of all values, including errors and criteria for not recommending values, is given in appendix 2. “Excluded values” column indicates that the specified HP techniques were not used in determining the given value. The bracketed numbers with the letters indicate the

samples for which the techniques were excluded and the reason the values were rejected. The following abbreviations were used under “Excluded values”:

1 = UF PC-1; 2 = WY PC-2; 3 = IL PC-3; 4 = PITT PC-4; 5 = POC PC-5; 6 = UT PC-6; 7 = WV PC-7; 8 = ND PC-8; o = determined value was an outlier;

s = only one significant figure in all determined values; f = values rejected because of forty percent rule (see text); and n = no values were determined or all

reported values were upper limits. All techniques referred to under “Excluded values” were determined on the ash except INAA, which was determined on

the whole coal (* indicates technique was done in Denver). —, no data] 

UF PC-1 WY PC-2 IL PC-3 PITT PC-4 POC PC-5 UT PC-6 WV PC-7 ND PC-8 No. HP

techniques

Excluded

values

Li ........... 14.8 4.0 7.8 8.6 5.6 5.3 28 2.69 2

Be .......... 1.5 (.25) (.76) (.77) .80 (.125) 2.0 (.175) 2 ICAP-AES* [2–4,6, 

8s]

B ............ (38) (96) (160) (47.8) (13.1) (127) (56) (79) 1

Sc........... 3.99 1.66 2.65 2.53 1.78 .78 7.5 (.80) 2 ICAP-AES* [8s]

V............ 26.5 14 35 16 11.5 4.3 43.3 3.7 2

Cr........... (22) (6.5) (36) (16) (10) 5.2 40 2.4 4 EDXRF [6n]

Co .......... 5.2 1.65 4.4 2.6 3.9 .93 7.8 (.78) 3 FAAS [8n],

ICAP-AES* [8s} 

Ni........... (15) (4.7) (19) 9.2 (7.6) 3.4 16 (1.5) 4 EDXRF [6n]; 

INAA [8n]

Cu .......... 18.9 13.0 10.1 5.8 (14) 4.1 (21) (4.2) 3 EDXRF [6n]

Zn .......... 20 11.0 (200) 8.3 (5) (6) 12 (5.2) 4 EDXRF [3f,6n]

Ga .......... (5.34) (1.9) (3.57) (3.3) (1.8) (1.00) (9.4) (1.16) 1

Ge .......... (4.35) (.36) (8.4) (1.2) (.29) (.23) (1.67) (.37) 1 

As .......... 16.7 (3.0) (4.2) 8.0 10.1 (.45) (6.4) (2.4) 2

Se........... (1.9) (2.0) (4.2) 1.6 (2.7) (1.2) 5.6 .59 2

Rb .......... 21 (2.7) 15.5 8.3 2.2 1.02 (36) (1.2) 3 INAA [2n,5n]; 

EDXRF [6n,8n]

Sr ........... (57) 257 (32) 64 (100) 64 (60) (560) 4 ICAP-AES [2f]; 

EDXRF [6n]

Y............ (9) 3.7 (4.1) (4.4) 6.3 2.0 11.7 (2.1) 3 EDXRF [6n,8n,7f]

Zr ........... 26 (21) (23) 19 16.5 (17.3) 75 (9) 2 EDXRF [6n]

Nb.......... 2.5 (1.2) (2.2) 1.8 (1.0) (.57) (7) (.79) 2 EDXRF [6n,8n]

Mo ......... (2.5) (.52) (6.3) (.74) (2.7) (.42) (1.27) (.41) 1

Ag.......... (.5) (.24) (.6) (.3) (.23) (.15) (1.2) (.15) 1

Cd .......... (.12) (.11) (.7) (.08) (.08) (.07) (.07) (.043) 2

Sn........... (.95) (.32) (.71) (.552) (.371) (.17) (1.75) (.4) 1

Sb........... .51 (.18) .84 (.22) (.4) (.10) .54 .15 2

Cs........... (1.7) .195 (1.1) .75 .24 .14 (2.1) (.09) 2

Ba .......... (56) 300 (83) (40) 200 35 (120) (500) 4 ICAP-AES [2f,5f]; 

EDXRF [6n]

La........... (9) (4.7) 6.0 (5.1) (6.2) (2.9) (19) (2.5) 3 EDXRF [2n,3n,5f, 

6n,8n]

Ce .......... 17 (8) (11) (10) (11) 4.7 (34) 4.3 3 EDXRF [6n,8n]

Pr ........... (1.9) (.93) (1.4) (1.12) (1.31) (.55) (4.1) (.43) 1

Nd.......... 7.7 (3.4) (4.9) (4.3) (5.0) (2.1) (14) (1.8) 2 INAA [2–5n]

Sm ......... (1.8) (.8) (1.1) (1.0) (1.1) (.44) (3.2) (.33) 2

Eu .......... .37 (.18) .21 (.19) .22 .092 .64 (.07) 2

Tb .......... .248 .11 .14 .12 .165 .056 .398 (.055) 2

Yb.......... .85 (.40) .52 .450 .56 .20 1.6 (.26) 2

Hf........... (.8) .64 (.7) (.56) (.50) .52 (2.1) (.38) 2

Ta........... .21 (.12) .18 (.15) .12 (.052) .63 (.093) 2 ICAP-MS* [8n]

W ........... (1.2) (.42) (1.73) .82 (1.0) .45 (1.7) (.36) 2

Pb........... 7.5 (2.3) (7) (3.4) (2.1) 1.52 12.1 (1.5) 2

Bi ........... (.117) (.053) (.088) (.117) (.051) (.035) (.23) — 1 ICAP-MS* [8n]

Th .......... (2.5) (1.6) 2.1 1.5 1.16 .60 6.4 (1.1) 2 ICAP-AES [8s]

U............ (1.0) .58 (5) (.5) (.57) .79 (1.9) .46 2
76 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

in tables 5 and 6. Values excluded from the determination of

recommended values and the reason for exclusion are given

in the final column of tables 5 and 6. After the analyses were

completed, 43 percent of the values reported in tables 5 and

6 were recommended values. 

CONCLUSIONS

A multitechnique approach is the best method to differentiate “good” values from “poor” values. Differences are

caused by spectral interferences, volatilization due to ashing, or incomplete sample dissolution. Interferences for a

given element usually differ for each technique. Losses

caused by volatilization can be determined by comparing

data from whole-coal procedures and ash procedures. Insolubility problems can be identified by comparing data from

techniques not requiring dissolution with data from techniques requiring dissolution. 

This paper does not recommend values for all elements, but it does provide reliable data for many trace elements. It provides manipulations of the data that will allow

readers to make their own interpretations and judgments. It

also demonstrates that some techniques are more reliable

than others for individual elements, and they depend on the

concentration of an element. This paper shows that the more

high-precision tests that can be run on a sample to measure

certain elements, the greater the reliability the data and the

greater the likelihood of determining a recommended value.

More important, it points out the uncertainties in attempting

to obtain reliable data from a single technique for coals of

widely differing types, it provides a basis for determining

some uncertainties of the techniques, and it should aid in the

evaluation of data determined by different techniques.

REFERENCES

American Society for Testing and Materials (ASTM), 1996,

ASTM Designation D 3174–93, Standard test method for ash

in the analysis sample of coal and coke from coal: 1996

Annual Book of ASTM Standards, v. 05.05, Gaseous fuels;

Coal and coke, p. 291–294.

Finkelman, R.B., Palmer, C.A., Krasnow, M.R., Aruscavage, P.J.,

Sellers, G.A., and Dulong, F.T., 1990, Combustion and leaching behavior of elements in the Argonne Premium Coal samples: Energy and Fuels, v. 4, no. 6, p. 755–767.

Kane, J.S., Arbogast, B.F., and Leventhal, J.S., 1990, Characterization of Devonian Ohio Shale SDO-1 and a geochemical reference sample: Geostandards Newsletter, v. 14, p. 169–196.

Taylor, J.K., 1987, Quality assurance of chemical measurements:

Chelsea, Mich., Lewis Publishers, Inc., 328 p.

Vorres, K.S., 1990, The Argonne Premium Coal Sample Program:

Energy and Fuels, v. 4, no. 5, p. 420–426.

———1993, Users handbook for the Argonne Premium Coal

Sample Program: Argonne National Laboratories Report

ANL/PCSP-93/1, 200 p.
Appendix 1. Comparison of the concentrations of 51 elements 

determined by multiple analytical techniques in 

8 Argonne Premium Coal samples.

Techniques.—The techniques include inductively coupled argon plasma-atomic

emission spectrometry (ICAP-AES) used in both Denver (D) and Reston (R) labs,

inductively coupled argon plasma-mass spectrometry (ICAP-MS), flame (FAAS) and

graphite furnace (GFAAS) atomic absorption spectrometry, hydride-generation atomic

absorption spectrometry (HGAAS), direct-current arc atomic emission spectrography

(DCAES), wavelength-dispersive (WDXRF) and energy-dispersive (EDXRF) X-ray

fluorescence spectrometry, and instrumental neutron activation analysis (INAA). 

Material analyzed.—Whole coal (WC) and ash were analyzed. Concentrations

originally reported on an ash basis were converted to a whole-coal basis, and

concentrations originally reported as an oxide were converted to an elemental basis for

ease of comparison. The ash yield was also reported. 

Location.—Materials were analyzed in U.S. Geological Survey laboratories in Denver

(D), Colo., and Reston (R), Va.

Concentrations.—The concentrations are reported as weight percent and parts per

million (ppm), which is equivalent to micrograms per gram.

Type styles and parentheses.—Average values in parentheses indicate that only one

value was reported. Techniques in bold type are high-precision techniques; concentrations

(except outliers) determined by these techniques are also in bold type. Techniques in

regular type are less precise than those in bold; concentrations determined by the lowprecision techniques are also in regular type. 

Outliers.—Concentrations in braces are considered outliers for the statistical analysis

used to determine the recommended values or the best average (see table 6 and appendix

2). Single outliers were determined by the Grubbs test (J.K. Taylor, 1987, Quality

assurance of chemical measurements, Chelsea, Mich., Lewis Publishers, Inc., 328 p.).

Multiple outliers for a given sample technique were determined by the 40 percent rule (see

paper by Palmer and Klizas, this volume). Values with one significant figure were treated

as outliers.

[Appendix 2 begins on p. 96]
78 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Ash (%) Si (weight percent) Al (weight percent)

Technique....................

Material analyzed........

Location ......................

550 ̊C

WC

R

ICAP-AES

Ash

D

WDXRF

Ash

R

DCAES

Ash

R

DCAES

WC

R

WDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

DCAES

WC

R

UF PC-1-1............... 13.5 2.5 2.64 3.0 3 1.54 1.61 1.5 2.0 2

UF PC-1-2............... 13.5 2.6 2.69 3.0 4 1.54 1.61 1.5 2.6 2

UF PC-1-3............... 13.5 2.7 — 3.4 3 — 1.59 1.6 2.6 2

AVG PC-1 ............... 13.5 2.6 2.67 3.1 3 1.54 1.60 1.6 2.4 2

WY PC-2-1 ............. 8.5 .99 1.23 1.3 .80 .675 .695 .63 .42 .47

WY PC-2-2 ............. 8.5 1.0 1.25 1.3 1.00 .670 .698 .63 .54 .54

WY PC-2-3 ............. 8.5 1.1 — 1.5 .52 — .705 .72 .61 .44

AVG PC-2 ............... 8.5 1.0 1.24 1.4 .77 .672 .699 .66 .53 .48

IL PC-3-1 ................ 16.2 3.1 3.04 3.6 3 1.21 1.26 {1.4} 1.9 2

IL PC-3-2 ................ 16.2 3.0 3.04 3.2 4 1.20 1.25 1.3 1.9 2

IL PC-3-3 ................ 16.2 {2.7} — 4.0 3 — 1.25 1.2 2.1 2

AVG PC-3 ............... 16.2 2.9 3.04 3.6 3 1.21 1.25 1.3 2.0 2

PITT PC-4-1............ 9.2 1.8 1.95 2.4 2 .988 .994 .97 2.2 1

PITT PC-4-2............ 9.2 1.8 1.97 2.7 3 .974 1.00 .97 1.9 2

PITT PC-4-3............ 9.2 1.8 — 2.9 2 — .994 {.92} 2.2 2

AVG PC-4 ............... 9.2 1.8 1.96 2.7 2 .981 .997 .96 2.1 2

POC PC-5-1 ............ 5.3 0.77 .810 .95 .83 .550 .551 {.59} .64 .80

POC PC-5-2 ............ 5.3 0.75 .798 .90 1.00 .547 .551 .56 .74 .92

POC PC-5-3 ............ 5.3 0.72 — 1.00 .80 — .546 .56 .74 .84

AVG PC-5 ............... 5.3 0.75 .804 .95 .88 .548 .549 .57 .71 .85

UT PC-6-1............... 4.6 .88 .893 .74 — .370 .348 .36 .31 —

UT PC-6-2............... — .92 — .92 — — .345 .39 .32 —

UT PC-6-3............... — .94 — .92 — — — .39 .29 —

AVG PC-6 ............... (4.6) .91 (.893) .86 — (.370) .347 .38 .32 —

WV PC-7-1 ............. 19.4 4.8 4.90 4.3 — 3.17 3.12 3.1 3.3 —

WV PC-7-2 ............. — 5.3 — 5.8 — — 3.18 3.2 4.3 —

WV PC-7-3 ............. — 5.0 — 5.4 — — 3.16 3.2 4.1 —

AVG PC-7 ............... (19.4) 5.0 (4.90) 5.2 — (3.17) 3.15 3.2 3.9 —

ND PC-8-1 .............. 9.5 .67 {.768} .54 — {.45} .396 .40 .21 —

ND PC-8-2 .............. — .67 — .63 — — .400 .40 .28 —

ND PC-8-3 .............. — .67 — .63 — — .404 .40 .21 —

AVG PC-8 ............... (9.5) .67 (0.768) .60 — (.45) .400 .40 .23 —
APPENDIX 1 79

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Fe (weight percent) Mg (weight percent)

Technique.....................

Material analyzed.........

Location .......................

INAA

WC

R

WDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

DCAES

WC

R

WDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

DCAES

WC

R

UF PC-1-1 .............. 1.76 1.98 1.86 1.6 1.6 2 0.079 0.082 0.075 0.13 0.097 

UF PC-1-2 .............. 1.81 1.88 1.89 1.7 1.3 3 .079 .082 .078 .15 .100 

UF PC-1-3 .............. 1.79 — 1.84 1.7 1.7 2 — .081 .080 .16 .100

AVG PC-1............... 1.78 1.93 1.86 1.7 1.6 2 .079 .082 .078 .15 .099

WY PC-2-1............. .381 .33 .358 .31 .26 .34 .25 .241 .20 .33 .20

WY PC-2-2............. .379 .32 .379 .35 .26 .33 .27 .236 .20 .39 .20

WY PC-2-3............. .339 — .363 .35 .31 .20 — — .23 .37 .20

AVG PC-2............... .366 .33 .367 .34 .27 .29 .26 .239 .21 .37 .20

IL PC-3-1................ 2.66 2.71 2.72 2.4 2.3 2 {.09} .076 .078 .11 .096

IL PC-3-2................ 2.67 2.70 2.66 2.5 2.3 2 {.09} .078 .075 .11 .099

IL PC-3-3................ 2.68 — 2.79 2.3 2.6 3 — .076 .068 .12 .100

AVG PC-3............... 2.67 2.70 2.72 2.4 2.4 2 .09 .077 .073 .12 .098

PITT PC-4-1........... 1.36 1.45 1.34 1.2 1.7 1 {.04} .038 .033 .065 .045

PITT PC-4-2........... 1.34 1.43 1.32 1.2 1.8 1 {.03} .038 .033 .064 .048

PITT PC-4-3........... 1.33 — 1.31 1.3 2.0 2 — .038 .033 .089 .052

AVG PC-4............... 1.35 1.44 1.32 1.2 1.9 1 .03 .038 .033 .073 .048

POC PC-5-1............ .504 .519 .513 .52 .52 .60 .067 .0562 .0575 .10 .079

POC PC-5-2............ .521 .522 .505 .48 .44 .80 .067 .0551 .0543 .11 .074

POC PC-5-3............ .502 — .504 .48 .53 .68 — .551 .0543 .11 .079

AVG PC-5............... .509 .521 .507 .50 .50 .69 .067 .0548 .0554 .11 .077

UT PC-6-1.............. .327 .29 .284 .29 .21 — .048 .030 .028 .043 —

UT PC-6-2.............. .310 — .281 .29 .27 — — .030 .031 .038 —

UT PC-6-3.............. .315 — — .31 .23 — — — .031 .041 —

AVG PC-6............... .317 (.29) .282 .30 .24 — (.048) .030 .030 .041 —

WV PC-7-1............. .404 .37 .396 .41 .35 — {.08} .092 .082 .128 —

WV PC-7-2............. .384 — .381 .39 .45 — — .095 .090 .084 —

WV PC-7-3............. .408 — .379 .38 .41 — — .096 .084 .078 —

AVG PC-7............... .399 (.37) .385 .39 .40 — (.08) .094 .085 .097 —

ND PC-8-1.............. .553 .45 .466 .45 .35 — .42 .395 .34 .52 —

ND PC-8-2.............. .529 — .470 .47 .43 — – .395 .355 .51 —

ND PC-8-3.............. .560 — .480 .46 .33 — – .405 .349 .51 —

AVG PC-8............... .547 (.45) .472 .46 .37 — (.42) .398 .351 .51 —
80 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Ca (weight percent) Na (weight percent)

Technique....................

Material analyzed........

Location ......................

WDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

DCAES

WC

R

INAA

WC

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

WDXRF

Ash

R

DCAES

Ash

R

UF PC-1-1............... 0.40 0.447 0.40 0.69 0.57 0.0336 0.032 0.034 {0.03} 0.042

UF PC-1-2............... .40 .445 .40 .59 .54 .0343 .032 .034 {.03} .047

UF PC-1-3............... — .443 .40 .63 .63 .0342 .032 .034 — .046

AVG PC-1 ............... .40 .445 .40 .64 .58 .0341 .032 .034 .03 .045

WY PC-2-1 ............. 1.10 1.21 1.0 1.0 1 .114 .119 .12 .10 .12

WY PC-2-2 ............. 1.15 1.16 .97 1.3 1 .117 .119 .12 .083 .16

WY PC-2-3 ............. — 1.22 1.1 1.4 1 .113 .119 .12 — .12

AVG PC-2 ............... 1.12 1.19 1.0 1.2 1 .115 .119 .12 .092 .13

IL PC-3-1 ................ .90 .943 .96 1.6 2 .103 .097 .11 .13 .16

IL PC-3-2 ................ .89 .965 .94 1.5 2 .101 .099 .11 {.09} .14

IL PC-3-3 ................ — .972 .87 1.8 1 .103 .094 .10 — .15

AVG PC-3 ............... .90 .960 .92 1.6 2 .102 .097 .11 (.13) .15

PITT PC-4-1............ .20 .211 .18 .46 .24 .0343 .032 .034 {.04} .039

PITT PC-4-2............ .20 .205 .18 .33 .34 .0342 .032 .034 {.03} .033

PITT PC-4-3............ — .203 .19 .43 .28 .0344 .031 .033 — .037

AVG PC-4 ............... .20 .206 .19 .41 .29 .0343 .032 .034 .03 .036

POC PC-5-1 ............ .443 .464 .45 .53 .69 .0797 .0832 .0826 .073 .13

POC PC-5-2 ............ .443 .452 .45 .58 .93 .0773 .0832 .0826 .069 .13

POC PC-5-3 ............ — .452 .45 .64 .79 .0778 .0816 .0826 — .13

AVG PC-5 ............... .443 .456 .45 .58 .80 .0782 .0826 .0826 .071 .13

UT PC-6-1............... .401 .418 {.35} .28 — .148 .127 .13 .13 .087

UT PC-6-2............... — .401 .43 .29 — .147 .124 .13 — .064

UT PC-6-3............... — — .43 .29 — .143 — .13 — .064

AVG PC-6 ............... (.401) .409 .43 .29 — .146 .126 .13 (.13) .072

WV PC-7-1 ............. {.06} .057 .056 .078 — {.0460} .033 .0346 {.05} .037

WV PC-7-2 ............. — .058 .061 .060 — .0351 .035 .0346 — .035

WV PC-7-3 ............. — .058 .058 .095 — .0352 .036 .0346 — .037

AVG PC-7 ............... (.06) .058 .058 .078 — .0388 .034 .0346 (.05) .036

ND PC-8-1 .............. 1.54 1.52 1.4 1.2 — .540 .460 .493 .50 —

ND PC-8-2 .............. — 1.53 1.4 1.3 — .533 .464 .493 — .25

ND PC-8-3 .............. — 1.57 1.4 1.4 — .515 .475 .493 — —

AVG PC-8 ............... (1.54) 1.54 1.4 1.3 — .529 .466 .493 (.50) (.25)
APPENDIX 1 81

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

K (weight percent) Ti (weight percent)

Technique....................

Material analyzed........

Location ......................

INAA

WC

R

WDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

WDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

DCAES

WC

R

UF PC-1-1 .............. 0.264 0.26 0.283 0.28 0.31 .078 0.078 0.072 0.061 0.10

UF PC-1-2 .............. .262 .28 .283 .30 .28 .082 .080 .074 .039 .10

UF PC-1-3 .............. .280 — .283 .29 .30 — .078 .078 .059 .10

AVG PC-1............... .269 .27 .283 .29 .30 .080 .079 .075 .053 .10

WY PC-2-1............. .0268 {.03} .028 .027 .031 .051 .056 .048 .030 .050

WY PC-2-2............. .0335 {.03} .028 .035 .037 .052 .056 .049 .037 .050

WY PC-2-3............. .0272 — .026 .038 .031 — .055 .056 .041 .038

AVG PC-2............... .0292 .03 .028 .033 .033 .051 .056 .051 .036 .044

IL PC-3-1................ .199 .21 .194 .23 .24 {.07} .070 .072 .062 .089

IL PC-3-2................ .186 .20 .194 .22 .26 {.07} .070 .071 .065 .100

IL PC-3-3................ .199 — .194 .22 .28 — .070 .064 .073 .086

AVG PC-3............... .195 .20 .194 .22 .26 .07 .070 .069 .066 .092

PITT PC-4-1........... .109 .11 .110 .11 .13 .059 .057 .051 .059 .086

PITT PC-4-2........... .112 .11 .110 .11 .12 .060 .056 .051 .052 .090

PITT PC-4-3........... .109 — .110 .11 .14 — .055 .049 .059 .097

AVG PC-4............... .110 .11 .110 .11 .13 .059 .056 .050 .057 .091

POC PC-5-1............ .0284 {.03} .027 .036 .034 .040 .038 .044 .028 .084

POC PC-5-2............ .026 {.03} .028 .036 .033 .039 .038 .038 .025 .084

POC PC-5-3............ .033 — .028 .032 .039 — .037 .038 .031 .078

AVG PC-5............... .029 .03 .028 .035 .036 .040 .038 .040 .028 .082

UT PC-6-1.............. .018 {.02} {.014} .027 .022 {.02} .023 .023 .018 —

UT PC-6-2.............. <.025 — {.014} .027 .014 — 0.023 .023 .020 —

UT PC-6-3.............. .0252 — — .029 .017 — .023 .018 —

AVG PC-6............... .022 (.02) .014 .028 .017 (.02) .023 .023 .019 —

WV PC-7-1............. .517 .46 .489 .46 .39 .24 .260 .22 .18 —

WV PC-7-2............. .497 — .501 .53 .33 — .260 .24 .18 —

WV PC-7-3............. .500 — .495 .48 .35 — .260 .23 .17 —

AVG PC-7............... .505 (.46) .495 .49 .36 (.24) .260 .23 .18 —

ND PC-8-1.............. .028 {.03} {.012} .044 .038 {.02} .020 .018 .017 —

ND PC-8-2.............. <.040 — {.016} .032 .033 — .019 .018 .017 —

ND PC-8-3.............. .030 — {.015} .036 .039 — .020 .020 .019 —

AVG PC-8............... .029 (.03) {.014} .037 .037 (.02) .020 .019 .018 —
82 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

P (weight percent) Mn (weight percent)

Technique....................

Material analyzed........

Location ......................

WDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

WDXRF

WC

R

DCAES

Ash

R

WDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

DCAES

WC

R

UF PC-1-1............... {0.005} 0.0076 0.0059 <0.005 <0.0092 <0.01 0.0041 0.0044 0.0055 0.0053

UF PC-1-2............... {.006} .0080 .0059 <.005 <.0092 <.01 .0042 .0044 .0051 .0059

UF PC-1-3............... — .0082 .0059 <.005 <.0092 — .0041 .0043 .0058 .0048

AVG PC-1 ............... .006 .0079 .0059 — — — .0041 .0044 .0055 .0053

WY PC-2-1 ............. {.03} .026 .021 .03 .020 <.007 .0020 .0020 .0042 .0010

WY PC-2-2 ............. {.03} .024 .021 .02 .026 <.007 .0021 .0020 .0027 .0016

WY PC-2-3 ............. — .026 .025 .03 .033 — .0019 .0019 .0031 .0014

AVG PC-2 ............... .03 .025 .022 .03 .026 — .0020 .0020 .0033 .0013

IL PC-3-1 ................ {.004} .0058 {.004} <.005 <.011 <.01 .0076 .0092 .011 .015

IL PC-3-2 ................ {.004} .0060 {.004} <.005 <.011 <.01 .0076 .0084 .010 .015

IL PC-3-3 ................ — .0060 {.003} <.005 <.011 — .0076 .0084 .011 .017

AVG PC-3 ............... .004 .0059 .004 — — — .0076 .0087 .011 .016

PITT PC-4-1............ {.01} .011 .0092 .009 <.0063 <.007 .0018 .0021 .0030 .0016

PITT PC-4-2............ {.01} .011 .0088 .009 <.0063 <.007 .0017 .0021 .0038 .0028

PITT PC-4-3............ — .011 .0060 .009 <.0063 — .0017 .0020 .0039 .0018

AVG PC-4 ............... .01 .011 .0080 .009 — — .0018 .0021 .0036 .0020

POC PC-5-1 ............ {.002} .0022 .0023 <.005 <.0036 <.004 .0016 .0018 .0024 .0016

POC PC-5-2 ............ {.002} .0022 .0023 <.005 <.0036 <.004 .0016 .0018 .0023 .0024

POC PC-5-3 ............ — .0021 {.002} <.005 <.0036 — .0016 .0019 .0026 .0017

AVG PC-5 ............... .002 .0022 .0023 — — — .0016 .0018 .0024 .0019

UT PC-6-1............... {.0001} .00092 {.0008} <.005 <.0031 <.004 .00041 .00043 .00064 —

UT PC-6-2............... — .00097 {.0008} <.005 <.0031 — .00041 .00042 .00046 —

UT PC-6-3............... — — {.0006} <.005 .00074 — — .00041 .00074 —

AVG PC-6 ............... (.001) .00094 .0007 — (.00074) — .00041 .00042 .00061 —

WV PC-7-1 ............. {.007} .0089 {.008} <.005 .017 <.015 .0016 .0014 .0018 —

WV PC-7-2 ............. — .0087 {.008} <.005 <.013 — .0015 .0014 .0023 —

WV PC-7-3 ............. — .0074 {.008} <.005 <.013 — .0015 .0014 .0019 —

AVG PC-7 ............... (.007) .0084 .008 — (.017) — .0015 .0014 .0020 —

ND PC-8-1 .............. {.02} .012 .012 .02 .012 {.007} .0080 .0081 .010 —

ND PC-8-2 .............. — .012 .012 .02 .010 — .0079 .0083 .010 —

ND PC-8-3 .............. — .012 .012 .02 .0093 — .0081 .0083 .010 —

AVG PC-8 ............... (.02) .012 .012 .02 .011 (.007) .0080 .0082 .010 —
APPENDIX 1 83

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Li (ppm) Be (ppm) B (ppm) 

Technique....................................

Material analyzed........................

Location ......................................

FAAS

Ash

R

ICAP-AES

Ash

D

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

UF PC-1-1 ............................. 15 15 1.5 1.5 1.5 35 19

UF PC-1-2 ............................. 15 15 1.5 1.5 1.2 31 47

UF PC-1-3 ............................. 15 15 1.5 1.5 1.5 49 24

AVG PC-1.............................. 15 15 1.5 1.5 1.4 38 30

WY PC-2-1............................ 4.1 3.9 .26 {.3} .14 85 74

WY PC-2-2............................ 4.2 3.9 .24 {.3} .14 110 63

WY PC-2-3............................ 4.1 3.9 .25 {.3} .15 94 73

AVG PC-2.............................. 4.1 3.9 .25 .3 .14 96 70

IL PC-3-1............................... 7.8 7.9 .78 {.6} .89 160 120

IL PC-3-2............................... 7.9 7.6 .75 {.6} .96 160 110

IL PC-3-3............................... 7.8 7.5 .75 {.6} 1.1 160 130

AVG PC-3.............................. 7.8 7.7 .76 .6 .97 160 120

PITT PC-4-1.......................... 8.7 9.2 .76 {.7} 1.1 48 49

PITT PC-4-2.......................... 8.6 8.3 .76 {.7} 1.2 49 53

PITT PC-4-3.......................... 8.6 8.2 .78 {.7} 1.2 47 52

AVG PC-4.............................. 8.6 8.9 .77 .7 1.2 48 51

POC PC-5-1........................... 5.8 5.3 .80 .80 .74 14 17

POC PC-5-2........................... 5.8 5.3 .80 .80 .58 13 16

POC PC-5-3........................... 5.8 5.8 .80 .80 .69 13 19

AVG PC-5.............................. 5.8 5.5 .80 .80 .67 13 17

UT PC-6-1............................. 5.1 5.5 .13 {.1} .15 120 <46

UT PC-6-2............................. 5.1 5.5 .12 {.1} .24 120 <46

UT PC-6-3............................. — 5.5 — {.1} .20 130 <46

AVG PC-6.............................. 5.1 5.5 .13 .1 .20 130 —

WV PC-7-1............................ 29 27 1.9 2.1 2.9 39 29

WV PC-7-2............................ 29 27.9 1.9 2.1 3.1 78 93

WV PC-7-3............................ 29 27 1.9 2.1 3.1 51 49

AVG PC-7.............................. 29 27 1.9 2.1 3.0 56 57

ND PC-8-1............................. 2.7 2.7 .18 {.2} .27 79 48

ND PC-8-2............................. 2.7 2.7 .17 {.2} .33 81 76

ND PC-8-3............................. 2.8 2.7 — {.2} .23 79 77

AVG PC-8.............................. 2.7 2.7 .18 .2 .28 79 67
84 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Sc (ppm) V (ppm)

Technique....................................

Material analyzed........................

Location ......................................

INAA

WC

R

ICAP-AES

Ash

D

DCAES

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

DCAES

WC

R

UF PC-1-1.............................. 4.04 3.9 2.6 26 27 18 38

UF PC-1-2.............................. 4.01 3.9 1.5 26 27 13 45

UF PC-1-3.............................. 4.14 3.9 2.2 26 27 17 41

AVG PC-1 .............................. 4.06 3.9 2.1 26 27 16 41

WY PC-2-1 ............................ 1.67 1.6 1.0 14 14 7.3 10

WY PC-2-2 ............................ 1.69 1.6 1.4 14 14 9.3 14

WY PC-2-3 ............................ 1.67 1.7 1.5 14 14 10.0 17

AVG PC-2 .............................. 1.68 1.6 1.3 14 14 9.0 14

IL PC-3-1 ............................... 2.55 2.8 2.5 32 39 23 52

IL PC-3-2 ............................... 2.57 2.8 2.6 32 37 23 59

IL PC-3-3 ............................... 2.64 2.6 2.8 31 36 26 44

AVG PC-3 .............................. 2.59 2.7 2.6 32 37 24 52

PITT PC-4-1........................... 2.61 2.5 1.8 15 17 12 20

PITT PC-4-2........................... 2.56 2.5 1.7 15 17 12 25

PITT PC-4-3........................... 2.55 2.5 2.0 15 17 14 27 

AVG PC-4 .............................. 2.57 2.5 1.9 15 17 13 24 

POC PC-5-1 ........................... 1.80 1.8 1.3 11 12 6.9 16

POC PC-5-2 ........................... 1.79 1.8 1.3 11 12 6.4 21

POC PC-5-3 ........................... 1.77 1.8 1.5 11 12 7.9 18

AVG PC-5 .............................. 1.79 1.8 1.3 11 12 7.1 18

UT PC-6-1.............................. .832 .78 .74 4.0 4.6 3.8 —

UT PC-6-2.............................. .801 .74 .69 4.0 4.4 3.6 —

UT PC-6-3.............................. .805 .74 .64 — 4.4 3.6 —

AVG PC-6 .............................. .813 .75 .69 4.0 4.5 3.7 —

WV PC-7-1 ............................ 7.69 7.4 7.0 43 43 31 —

WV PC-7-2 ............................ 7.54 7.4 6.0 45 43 35 —

WV PC-7-3 ............................ 7.61 7.4 6.2 43 43 29 —

AVG PC-7 .............................. 7.62 7.4 6.4 44 43 32 —

ND PC-8-1 ............................. .846 {.8} .87 3.5 3.9 3.6 —

ND PC-8-2 ............................. .828 {.8} .86 3.4 3.8 3.6 —

ND PC-8-3 ............................. .865 {.8} .95 3.6 3.9 3.5 —

AVG PC-8 .............................. .846 .8 .90 3.5 3.9 3.6 —
APPENDIX 1 85

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Cr (ppm) Co (ppm)

Technique..................

Material analyzed......

Location ....................

INAA

WC

R

EDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

EDXRF

WC

R

DCAES

Ash

R

DCAES

WC

R

INAA

WC

R

FAAS

Ash

R

ICAP-AES

Ash

D

DCAES

Ash

R

DCAES

WC

R

UF PC-1-1 ............. 20.4 25.1 20 22 15 22 32 5.27 5.1 5.3 3.8 5

UF PC-1-2 ............. 20.3 26.5 19 22 23 17 38 5.41 5.1 5.3 3.0 5

UF PC-1-3 ............. 20.4 26.5 20 22 19 19 26 5.31 4.7 5.4 3.9 5

AVG PC-1.............. 20.3 26.0 20 22 19 19 32 5.33 5.0 5.3 3.5 5

WY PC-2-1............ 5.7 7.3 6.2 6.3 3 4.8 8 1.66 1.6 1.5 1.0 <5

WY PC-2-2............ 6.22 8.2 6.4 6.5 5 6.3 6 1.73 1.6 1.8 1.4 <5

WY PC-2-3............ 6.23 {9.18} 6.0 6.4 — 5.9 8 1.65 1.6 1.7 1.4 <5

AVG PC-2.............. 6.1 8.2 6.2 6.4 4 5.7 7 1.68 1.6 1.7 1.3 —

IL PC-3-1............... 33.7 42.9 29 41 29 36 54 4.21 4.2 4.7 3.6 <5

IL PC-3-2............... 32.5 42.9 32 34 36 36 57 4.21 4.5 4.4 3.4 <5

IL PC-3-3............... 33.2 43.7 31 34 41 42 47 4.53 4.2 4.2 4.2 <5

AVG PC-3.............. 33.1 43.2 31 36 35 38 52 4.31 4.3 4.4 3.7 —

PITT PC-4-1.......... 15.0 18.4 15 16 6 20 23 2.65 2.4 2.6 2.8 <5

PITT PC-4-2.......... 15.0 17.5 14 16 10 17 27 2.61 2.6 2.7 2.3 <5

PITT PC-4-3.......... 14.5 17.9 13 16 9 20 21 2.60 2.4 2.6 2.8 <5

AVG PC-4.............. 14.8 17.9 14 16 8 19 24 2.62 2.4 2.6 2.6 —

POC PC-5-1........... 9.3 12.5 9.5 10.1 5 9.0 17 4.09 3.8 4.0 2.4 5

POC PC-5-2........... 9.06 11.9 8.5 9.5 7 8.0 17 4.13 3.8 3.9 2.3 5

POC PC-5-3........... 8.85 12.5 9.5 9.5 4 9.5 14 3.98 3.8 4.0 3.0 5

AVG PC-5.............. 9.1 12.3 9.2 9.7 5 8.8 16 4.07 3.8 4.0 2.6 5

UT PC-6-1............. 5.25 — 5.1 5.5 <10 5.1 — 1.01 .83 .97 .69 —

UT PC-6-2............. 5.03 — 4.6 5.1 <10 3.9 — .992 .83 .92 .60 —

UT PC-6-3............. 5.62 — — 5.1 <10 5.5 — 1.00 — .92 .64 —

AVG PC-6.............. 5.30 — 4.8 5.2 — 4.8 — 1.00 .83 .94 .64 —

WV PC-7-1............ 36.2 46.2 41 39 50 43. — 7.65 7.8 7.4 7.0 —

WV PC-7-2............ 35.6 45.4 41 39 48 35 — 7.86 8.4 7.6 5.8 —

WV PC-7-3............ 35.7 46.0 39 39 48 41 — 7.72 8.2 7.4 6.0 —

AVG PC-7.............. 35.8 45.9 40 39 49 39 — 7.74 8.1 7.5 6.3 —

ND PC-8-1............. 2.23 2.5 2.6 2.2 <10 2.4 — .771 <1 {.8} .54 —

ND PC-8-2............. 2.16 2.7 2.5 2.2 <10 2.4 — .761 <1 {1} .57 —

ND PC-8-3............. 2.33 2.8 2.3 2.5 <10 2.5 — .802 <1 {.8} .54 —

AVG PC-8.............. 2.24 2.6 2.4 2.3 — 2.4 — .778 — .9 .55 —
86 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Ni (ppm) Cu (ppm))

Technique................

Material analyzed ...

Location ..................

INAA

WC

R

EDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

EDXRF

WC

R

DCAES

Ash

R

DCAES

WC

R

EDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

EDXRF

WC

R

DCAES

Ash

R

DCAES

WC

R

UF PC-1-1............ 15.9 14.0 15 15 27 14 22 19.7 19 19 20 17 20

UF PC-1-2............ 13.2 15.9 14 15 22 13 29 20.5 19 19 18 16 18

UF PC-1-3............ 14.3 11 15 15 21 14 24 21.3 19 18 17 19 16

AVG PC-1............ 14.5 14 14 17 23 14 25 20.4 19 19 18 17 18

WY PC-2-1.......... 4.4 4.3 4.9 4.7 9 4.8 <10 12.1 12 13 18 11 5.0

WY PC-2-2.......... 5.4 3.9 4.7 4.9 7 5.4 <10 13.4 12 14 17 14 10

WY PC-2-3.......... 5.0 3.7 5.2 4.7 8 5.4 <10 13.1 13 14 17 14 6.0

AVG PC-2............ 4.9 3.9 4.9 4.8 8 5.2 — 12.9 12 14 17 13 7

IL PC-3-1............. 24.2 14 18 {29} 33 21 28 11 10 11 15 13 9.0

IL PC-3-2............. 17.8 20 19 19 30 19 35 9.4 10 11 13 11 10

IL PC-3-3............. 21.0 19 18 19 33 24 37 8.7 10 10 15 9.4 9.0

AVG PC-3............ 21.0 18 18 19 32 22 33 9.6 10 11 14 11 9

PITT PC-4-1 ........ 9.4 9.0 9.1 8.9 17 14 13 6.4 5.5 5.4 10 5.3 5.0

PITT PC-4-2 ........ 11.3 8.8 8.3 9.2 11 12 14 6.1 5.3 6.2 9 8.2 6.0

PITT PC-4-3 ........<12 10.3 8.1 9.2 15 13 11 6.1 5.5 5.7 10 6.1 7.0

AVG PC-4............ 10.3 9.3 8.5 9.1 14 13 12 6.2 5.5 5.8 10 6.5 6

POC PC-5-1......... 9.2 7.00 6.9 7.4 11 6.4 11 12.7 12 16 16 22 18

POC PC-5-2......... 8.5 7.74 6.4 7.4 9 5.8 11 13.0 12 16 16 15 13

POC PC-5-3......... 8.2 8.0 6.9 7.4 12 7.4 <10 11.9 12 16 19 20 27

AVG PC-5............ 8.6 7.58 6.7 7.4 11 6.5 11 12.5 12 16 17 19 19

UT PC-6-1 ........... <3 — 3.4 3.6 5 3.9 — — 3.9 4.3 8 3.2 —

UT PC-6-2 ........... 3.2 — 3.3 3.4 5 4.1 — — 3.8 4.2 8 2.4 —

UT PC-6-3 ........... 3.7 — — 3.5 5 4.0 — — — 4.1 8 3.0 —

AVG PC-6............ 3.4 — 3.3 3.5 5 4.0 — — 3.8 4.2 8 2.9 —

WV PC-7-1.......... 14.0 18 16 16 17 23 — 25.2 19 21 30 17 —

WV PC-7-2.......... 18 16 16 16 18 19 — 22.3 19 21 30 16 —

WV PC-7-3.......... 14.3 17 16 16 19 21 — 23.3 19 21 32 13 —

AVG PC-7............ 15.4 17 16 16 18 21 — 23.6 19 21 31 16 —

ND PC-8-1........... <5 2.4 1.4 1.3 4 1.6 — 3.4 5.6 4.5 8 3.9 —

ND PC-8-2........... <3 1.6 1.4 1.5 10 1.6 — 3.3 3.5 4.8 10 3.8 —

ND PC-8-3........... <3 1.8 1.1 1.4 4 2.1 — 3.2 4.9 {12} 10 7.1 —

AVG PC-8............ — 1.9 1.3 1.4 6 1.8 — 3.3 4.7 4.6 9 4.9 —
APPENDIX 1 87

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Zn (ppm) Ga (ppm) Ge (ppm)

Technique.................

Material analyzed.....

Location ...................

INAA

WC

R

EDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

EDXRF

WC

R

DCAES

WC

R

ICAP-MS

Ash

D

DCAES

Ash

R

DCAES

WC

R

ICAP-MS

Ash

D

DCAES

Ash

R

DCAES

WC

R

UF PC-1-1 ............ 18.2 21.9 19 19 35 30 5.45 6.1 11 4.39 3.5 4

UF PC-1-2 ............ 17.0 19.2 19 19 32 30 5.21 6.3 11 4.29 3.4 4

UF PC-1-3 ............ 23.9 20.3 20 19 31 40 5.35 6.3 8 4.37 3.9 3

AVG PC-1............. 19.7 20.5 19 19 33 33 5.34 6.2 10 4.35 3.6 4

WY PC-2-1........... 11.0 9.7 10 13 26 <20 1.86 2.2 4 .36 <.4 <2

WY PC-2-2........... 11.6 11.1 10 11 29 <20 1.82 2.6 2 .36 <.4 <2

WY PC-2-3........... 11.2 11.1 10 12 21 <20 2.04 2.5 3 .36 <.4 <2

AVG PC-2............. 11.3 10.6 10 12 25 — 1.91 2.4 3 .36 — —

IL PC-3-1.............. 218 {94} 160 180 137 250 3.45 4.7 8 8.10 8.4 8

IL PC-3-2.............. 243 {112} 180 210 105 260 3.64 4.4 5 8.62 8.4 7

IL PC-3-3.............. 200 {115} 190 190 186 320 3.63 5.0 7 8.49 9.7 12

AVG PC-3............. 220 107 180 190 140 280 3.57 4.7 7 8.40 8.9 9

PITT PC-4-1......... 8.9 8.5 8.2 {14} 17 20 3.17 5.2 6 1.13 1.2 3

PITT PC-4-2......... 7.8 8.5 7.4 8.1 14 30 3.24 4.0 5 1.22 1.2 <2

PITT PC-4-3......... 10.5 8.1 7.7 8.1 15 30 3.44 5.0 5 1.39 1.1 <2

AVG PC-4............. 9.1 8.4 7.8 8.1 15 27 3.28 4.7 5 1.25 1.2 (3)

POC PC-5-1.......... 5.74 4.3 3.9 5.3 14 <20 1.70 2.2 4 .23 .46 <2

POC PC-5-2.......... 6.15 5.3 4.1 5.3 14 <20 1.80 2.1 3 .27 .43 <2

POC PC-5-3.......... 7.3 4.7 3.9 5.3 15 <20 1.89 2.5 4 .36 .49 <2

AVG PC-5............. 6.4 4.8 4.0 5.3 14 — 1.80 2.3 4 .29 .46 —

UT PC-6-1............ 4.80 — 6.4 4.6 <2 — .948 1.5 — .19 <.2 —

UT PC-6-2............ 7.43 — 6.0 5.1 <2 — .989 .9 — .24 <.2 —

UT PC-6-3............ 6.82 — — 4.6 <2 — 1.05 1.3 — .25 <.2 —

AVG PC-6............. 6.35 — 6.2 4.8 — — 1.00 1.2 — .23 — —

WV PC-7-1........... 14.0 12 13 11 9 — 8.88 13 — 1.6 1.1 —

WV PC-7-2........... 12.5 11 13 11 10 — 9.62 11 — 1.7 <.89 —

WV PC-7-3........... 14.0 12 12 11 10 — 9.66 11 — 1.7 1.2 —

AVG PC-7............. 13.5 12 13 11 10 — 9.39 12 — 1.7 1.1 —

ND PC-8-1............ 5.71 5.8 5.1 5.1 5 — 1.21 1.8 — .32 <.44 —

ND PC-8-2............ 5.5 5.1 4.7 4.7 4 — 1.14 1.5 — .37 <.44 —

ND PC-8-3............ 5.86 5.2 4.5 4.7 6 — 1.14 1.9 — .41 <.44 —

AVG PC-8............. 5.69 5.4 4.6 4.8 5 — 1.16 1.7 — .37 — —
88 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

As (ppm) Se (ppm) Rb (ppm)

Technique.......................

Material analyzed...........

Location .........................

INAA

WC

R

ICAP-MS

Ash

D

DCAES

Ash

R

INAA

WC

R

HGAAS

WC

D

INAA

WC

R

ICAP-MS

Ash

D

EDXRF

Ash

R

EDXRF

WC

R

UF PC-1-1.................. 16.6 16.4 31 2.09 2.3 19.4 22.9 21.6 23

UF PC-1-2.................. 17.6 15.9 38 1.88 2.0 19.0 21.6 20.8 21

UF PC-1-3.................. 17.1 16.1 22 1.8 1.5 20.0 21.6 21.3 20

AVG PC-1.................. 17.1 16.1 30 1.92 1.9 19.5 22.0 21.2 21

WY PC-2-1................ 3.67 2.8 <9 1.57 1.8 <5 1.80 3.4 14

WY PC-2-2................ 3.23 2.6 <9 1.49 2.8 <5 1.80 3.4 14

WY PC-2-3................ 3.75 1.9 <9 1.63 2.5 <5 1.80 3.7 11

AVG PC-2.................. 3.6 2.4 — 1.56 2.4 — 1.80 3.5 13

IL PC-3-1................... 4.46 3.6 <16 3.78 4.1 15.5 15.6 15 22

IL PC-3-2................... 4.65 3.7 <16 4.03 4.0 17.2 16.0 15 17

IL PC-3-3................... 4.90 4.0 <16 5.07 4.3 14.6 15.6 15 21

AVG PC-3.................. 4.7 3.8 — 4.29 4.1 16 15.7 15 20

PITT PC-4-1 .............. 8.44 7.1 19 1.49 1.8 9.0 8.00 9.38 8

PITT PC-4-2 .............. 8.30 7.6 17 1.60 1.6 7.2 8.06 8.6 8

PITT PC-4-3 .............. 8.5 8.2 15 1.34 1.6 7.1 8.30 9.20 8

AVG PC-4.................. 8.42 7.6 17 1.5 1.7 7.7 8.12 9.1 8

POC PC-5-1............... 10.4 9.33 18 2.3 2.9 <6 2.04 2.6 5

POC PC-5-2............... 10.6 9.81 11 2.5 2.9 <6 2.11 2.1 4

POC PC-5-3............... 9.89 10.5 14 2.60 3.1 <3 2.18 2.2 5

AVG PC-5.................. 10.3 9.9 15 2.5 3.0 — 2.11 2.3 5

UT PC-6-1 ................. .51 .33 <10 1.03 1.2 <2 1.01 — 3

UT PC-6-2 ................. .50 <.05 <10 1.16 1.3 1.00 1.06 — 2

UT PC-6-3 ................. .44 <.05 <10 1.03 1.3 .95 1.10 — 3

AVG PC-6.................. .48 (.33) — 1.08 1.3 .98 1.06 — 3

WV PC-7-1................ 5.8 6.4 <43 5.3 6.1 29.8 35.0 42.3 43

WV PC-7-2................ 5.29 6.6 <43 5.54 5.6 28.5 36.9 45.0 43

WV PC-7-3................ 7.40 7.2 <43 5.5 {6.9} 31.2 36.9 43.4 40

AVG PC-7.................. 6.2 6.7 — 5.4 5.8 29.7 36.3 43.6 42

ND PC-8-1................. 2.67 1.6 <21 .51 .60 .86 1.37 — 4

ND PC-8-2................. 2.61 {.70} <21 .61 .60 .99 1.41 — 5

ND PC-8-3................. 2.61 <.1 <21 .63 .60 <1 1.46 — 3

AVG PC-8.................. 2.63 (1.6) — .58 .60 .93 1.41 — 4
APPENDIX 1 89

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Sr (ppm) Y (ppm)

Technique....................

Material analyzed........

Location ......................

INAA

WC

R

EDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

EDXRF

WC

R

DCAES

Ash

R

EDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

EDXRF

WC

R

DCAES

Ash

R

UF PC-1-1 .............. 56 59 59 58 61 66 10 9.3 8.5 — 6.2

UF PC-1-2 .............. 58 61 61 58 63 57 9.7 9.3 8.1 — 3.0

UF PC-1-3 .............. 33 61 58 58 61 66 11 9.2 7.6 — 4.9

AVG PC-1............... 49 60 59 58 62 63 10 9.3 8.1 — 4.7

WY PC-2-1............. 263 260 {153} 260 292 170 3.4 3.9 3.6 — 2.4

WY PC-2-2............. 248 260 {145} 260 300 240 3.6 3.7 3.6 — 3.1

WY PC-2-3............. 245 260 {153} 260 291 260 3.7 3.7 3.7 — 3.6

AVG PC-2............... 252 260 150 260 294 220 3.6 3.8 3.6 — 3.0

L PC-3-1................. 42 30.5 29 31 33 40 4.9 4.2 4.2 — 4.4

IL PC-3-2................ 36 28.8 29 32 30 37 3.2 4.2 4.2 — 4.7

IL PC-3-3................ 40 30.5 29 31 35 44 4.2 4.2 3.7 — 5.2

AVG PC-3............... 39 29.9 29 31 33 40 4.1 4.2 4.0 — 4.7

PITT PC-4-1........... 58 70 64 64 59 88 5.1 4.3 4.0 — 2.8

PITT PC-4-2........... 61 68 64 64 61 83 5.1 4.2 3.9 — 3.3

PITT PC-4-3........... 65 65 63 63 69 100 4.4 4.2 4.0 — 3.0

AVG PC-4............... 61 68 64 64 63 91 4.9 4.3 4.0 — 3.1

POC PC-5-1............ 97 110 85 110 86 110 7.10 6.4 5.8 — 4.6

POC PC-5-2............ 116 110 85 110 77 100 6.68 6.4 5.8 — 4.3

POC PC-5-3............ 101 110 85 110 93 120 6.89 5.8 5.8 — 4.9

AVG PC-5............... 105 110 85 110 85 110 6.89 6.2 5.8 — 4.6

UT PC-6-1.............. 71 — 60 60 58 83 — 1.8 2.1 2 1.9

UT PC-6-2.............. 68 — 59 60 65 92 — 2.1 2.0 <2 1.9

UT PC-6-3.............. 70 — — 60 66 92 — — 2.0 <2 1.6

AVG PC-6............... 70 — 60 60 63 89 — 2.0 2.0 (2) 1.8

WV PC-7-1............. 64 76.2 49 62 87 76 {21.4} 11 12 19 9.7

WV PC-7-2............. 59 78.0 47 62 87 62 {19} 11 13 20 10

WV PC-7-3............. 58 79.7 51 62 83 72 {22.9} 11 12 17 7.6

AVG PC-7............... 60 78.0 49 62 86 70 21.2 11 12 19 9.1

ND PC-8-1.............. 628 640 510 490 800 590 — 1.9 2.2 <2 2.3

ND PC-8-2.............. 580 640 500 490 800 600 — 1.8 2.3 <2 2.6

ND PC-8-3.............. 583 630 500 490 750 690 — — 2.2 <2 2.4

AVG PC-8............... 597 640 500 490 780 630 — 1.8 2.2 — 2.4
90 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Zr (ppm) Nb (ppm) Mo (ppm)

Technique....................

Material analyzed........

Location ......................

ICAP-AES

Ash

D

EDXRF

Ash

R

EDXRF

WC

R

DCAES

Ash

R

DCAES

WC

R

ICAP-MS

Ash

D

EDXRF

Ash

R

EDXRF

WC

R

DCAES

Ash

R

ICAP-MS

Ash

D

DCAES

Ash

R

UF PC-1-1............... 24 27.7 24 13 36 2.6 2.7 — 1.6 3.02 1.6

UF PC-1-2............... 24 26.5 22 7.4 29 2.3 2.2 — 1.3 2.24 1.3

UF PC-1-3............... 25 27.7 24 12 34 2.4 2.7 — 2.0 2.23 1.6

AVG PC-1 ............... 24 27.3 23 11 33 2.4 2.5 — 1.7 2.50 1.5

WY PC-2-1 ............. 18 22.1 19 12 <20 1.4 1.2 — 1.2 .52 .65

WY PC-2-2 ............. 19 23.4 21 17 <20 1.3 1.0 — 1.3 .49 .66

WY PC-2-3 ............. 20 22.5 17 21 <20 1.5 .85 — 1.8 .54 .70

AVG PC-2 ............... 19 22.7 19 17 — 1.4 1.0 — 1.4 .52 .67

IL PC-3-1 ................ 28 23.7 24 14 22 1.9 1.9 — 19 7.24 5.5

IL PC-3-2 ................ 23 21.1 22 16 25 2.3 <1.6 — 2.3 5.57 4.9

IL PC-3-3 ................ 19 22.0 24 23 16 2.4 2.3 — 3.2 6.06 5.2

AVG PC-3 ............... 23 22.3 23 17 21 2.2 2.1 — 2.5 6.23 5.2

PITT PC-4-1............ 18 20.7 15 10 23 1.6 2.0 — 1.7 .71 .86

PITT PC-4-2............ 18 21.2 17 15 21 1.7 1.8 — 2.0 .73 .70

PITT PC-4-3............ 18 19.8 18 11 28 1.8 1.8 — 1.7 .77 .83

AVG PC-4 ............... 18 20.5 17 12 24 1.7 1.9 — 1.8 .74 .80

POC PC-5-1 ............ 17 17.0 10 13 25 1.0 .85 — 1.3 2.61 2.0

POC PC-5-2 ............ 16 16.7 8 11 34 1.1 .85 — .74 2.65 2.2

POC PC-5-3 ............ 15 17.0 11 12 32 1.3 .85 — 1.2 2.85 2.4

AVG PC-5 ............... 16 16.9 10 12 30 1.1 .85 — 1.1 2.67 2.2

UT PC-6-1............... 17 — 20 12 — .51 — <10 .46 .41 .55

UT PC-6-2............... 18 — 17 13 — .55 — <10 .51 .41 .39

UT PC-6-3............... 17 — 16 9.2 — .64 — <10 .55 .45 .51

AVG PC-6 ............... 17 — 18 11 — .57 — — .51 .42 .48

WV PC-7-1 ............. 66 80.0 106 47 — 5.6 7.8 13 2.5 1.2 1.3

WV PC-7-2 ............. 74 79.8 102 29 — 6.0 8.3 <10 3.7 1.3 1.6

WV PC-7-3 ............. 68 81.6 101 27 — 6.6 8.9 13 4.5 1.3 1.2

AVG PC-7 ............... 69 80.5 103 34 — 6.1 8.3 13 3.6 1.3 1.4

ND PC-8-1 .............. 11 6.5 20 12 — .74 <1 <10 .63 .39 .82

ND PC-8-2 .............. 13 7.0 19 12 — .80 <1 <10 .51 .42 .78

ND PC-8-3 .............. 12 4.5 17 13 — .84 <1 <10 .61 .44 .83

AVG PC-8 ............... 12 6.5 18 13 — .79 — — .58 .42 .81
APPENDIX 1 91

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Ag (ppm) Cd (ppm) Sn (ppm) Sb (ppm) Cs (ppm)

Technique....................

Material analyzed........

Location ......................

ICAP-MS

Ash

D

DCAES

Ash

R

ICAP-MS

Ash

D

GFAAS

Ash

R

ICAP-MS

Ash

D

DCAES

Ash

R

INAA

WC

R

ICAP-MS

Ash

D

INAA

WC

R

ICAP-MS

Ash

D

UF PC-1-1 .............. 0.36 0.19 0.14 0.072 0.96 1.76 0.558 0.51 1.48 1.89

UF PC-1-2 .............. .40 .20 .22 .069 .97 1.62 .50 .46 1.52 1.89

UF PC-1-3 .............. .62 .22 .14 .073 .95 1.62 .535 .50 1.56 1.89

AVG PC-1............... .46 .21 .17 .071 .96 1.67 .531 .49 1.52 1.89

WY PC-2-1............. .17 .055 .10 .094 .32 .544 .180 .15 .180 .19

WY PC-2-2............. .20 .072 .11 .094 .32 .85 .203 .15 .203 .20

WY PC-2-3............. .33 .075 .15 .094 .32 1.2 .191 .18 .191 .19

AVG PC-2............... .23 .067 .12 .094 .32 .86 .191 .16 .191 .19

IL PC-3-1................ .44 .356 .67 .60 .70 1.6 .848 .73 .848 1.4

IL PC-3-2................ .62 .421 .76 .65 .75 2.4 .913 .81 .913 1.4

IL PC-3-3................ .79 .324 .94 .57 .70 3.2 .870 .84 .870 1.4

AVG PC-3............... .62 .367 .79 .61 .72 2.4 .877 .79 .877 1.4

PITT PC-4-1........... .18 .087 .10 .059 .57 1.7 .239 .18 .737 .80

PITT PC-4-2........... .29 .086 .092 .058 .57 1.0 .240 .20 .69 .81

PITT PC-4-3........... .44 .092 .13 .063 .58 1.2 .221 .21 .67 .80

AVG PC-4............... .31 .088 .11 .061 .57 1.3 .233 .20 .70 .80

POC PC-5-1............ .14 .095 {.034} .085 .37 148 .625 .29 .256 .23

POC PC-5-2............ .22 .095 .053 .074 .37 29 .458 .29 .283 .23

POC PC-5-3............ .32 .106 .090 .074 .38 38 .535 .32 .247 .22

AVG PC-5............... .23 .099 .072 .078 .37 72 .539 .27 .262 .22

UT PC-6-1.............. .097 .55 .064 .060 .17 .40 .118 .087 .123 .14

UT PC-6-2.............. .17 .41 .078 .060 .17 .28 .098 .087 .148 .14

UT PC-6-3.............. .19 .44 .087 — .16 .43 .106 .092 .119 .14

AVG PC-6............... .15 .47 .077 .060 .16 .37 .107 .089 .130 .14

WV PC-7-1............. .70 .50 .050 .078 1.7 2.13 .521 .52 1.88 2.33

WV PC-7-2............. 1.2 .43 .044 .072 1.7 1.61 .540 .54 1.87 2.33

WV PC-7-3............. 1.8 .43 .072 .085 1.7 1.94 .502 .62 1.84 2.33

AVG PC-7............... 1.2 .45 .055 .078 1.7 1.9 .521 .56 1.86 2.33

ND PC-8-1.............. .095 <.0095 .029 .048 .28 <.5 .148 .13 .072 .10

ND PC-8-2.............. .15 <.0095 .043 .044 .28 <.5 .155 .14 .097 .095

ND PC-8-3.............. .22 <.0095 .049 .046 .56 1.23 .158 .19 .089 .10

AVG PC-8............... .16 — .040 .046 .38 (1.23) .153 .16 .086 .10
92 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Ba (ppm) La (ppm)

Technique...............

Material analyzed...

Location .................

INAA

WC

R

EDXRF

Ash

R

ICAP-AES

Ash

R

ICAP-AES

Ash

D

EDXRF

WC

R

DCAES

Ash

R

DCAES

WC

R

INAA

WC

R

ICAP-MS

Ash

D

EDXRF

Ash

R

EDXRF

WC

R

DCAES

Ash

R

UF PC-1-1........... 52 51 54 53 54 40 88 10.0 6.8 7.0 31 8.6

UF PC-1-2........... 68 54.7 55 51 68 43 72 10.0 8.1 8.1 9 5.3

UF PC-1-3........... 63 50 57 63 59 39 84 10.3 8.1 9.5 9 6.7

AVG PC-1 ........... 61 52 55 56 60 41 81 10.1 7.7 8.2 16 6.9

WY PC-2-1 ......... 324 270 {15} 280 404 290 200 5.32 4.2 <3 4 4.8

WY PC-2-2 ......... 318 280 {15} 290 407 310 260 5.34 3.4 <3 4 6.5

WY PC-2-3 ......... 297 260 {14} 310 415 360 300 5.38 4.3 <3 11 7.1

AVG PC-2 ........... 310 270 15 290 410 320 250 5.35 4.0 — 6 6.1

IL PC-3-1 ............ 94 75.3 68 83 112 51 140 6.11 6.5 <5 16 8.7

IL PC-3-2 ............ 91 74.5 87 77 122 53 120 6.10 6.5 <5 15 8.9

IL PC-3-3 ............ 96 73.7 87 86 129 76 92 6.09 4.8 <5 15 10

AVG PC-3 ........... 94 74.5 81 82 121 60 120 6.10 5.9 — 15 9.3

PITT PC-4-1........ 44 34.0 42 39 46 36 66 6.19 4.6 <3 23 5.5

PITT PC-4-2........ 51 37.7 41 39 22 34 72 6.15 4.6 4.6 1 6.1

PITT PC-4-3........ 44 35.4 39 38 19 45 60 6.11 4.6 4.2 2 5.7

AVG PC-4 ........... 47 35.7 41 39 29 38 66 6.15 4.6 4.4 9 5.8

POC PC-5-1 ........ 197 170 {16} 220 134 190 400 6.78 5.98 {1.6} 1 6.9

POC PC-5-2 ........ 203 190 {16} 200 124 190 460 6.77 5.61 {2.6} 4 6.9

POC PC-5-3 ........ 193 180 {16} 200 164 260 500 6.73 5.41 {2.3} 10 7.9

AVG PC-5 ........... 198 180 16 210 140 210 450 6.76 5.67 2.2 5 7.2

UT PC-6-1........... 36 — 32 33 28 34 — 3.41 2.3 — 9 3.0

UT PC-6-2........... 37 — 30 34 32 31 — 3.27 2.8 — 9 2.9

UT PC-6-3........... 36 — — 37 28 41 — 3.24 2.3 — 11 2.9

AVG PC-6 ........... 36 — 31 35 29 36 — 3.31 2.5 — 10 2.9

WV PC-7-1 ......... 166 110 120 110 230 130 — 21.7 17 15 15 14

WV PC-7-2 ......... 116 112 120 140 202 140 — 21.6 18 18 18 14

WV PC-7-3 ......... 116 107 130 120 200 120 — 21.3 17 19 14 12

AVG PC-7 ........... 133 110 120 120 210 130 — 21.5 17 17 16 14

ND PC-8-1 .......... 699 480 430 520 1,000 500 — 2.79 1.9 — 8 3.5

ND PC-8-2 .......... 660 470 390 530 1,040 700 — 2.84 1.9 — 6 3.8

ND PC-8-3 .......... 671 450 450 530 1,060 540 — 2.84 1.9 — 10 3.7

AVG PC-8 ........... 680 460 420 530 1,030 580 — 2.82 1.9 — 8 3.7
APPENDIX 1 93

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Ce (ppm) Pr (ppm) Nd (ppm) Sm (ppm)

Technique...............

Mat. analyzed.........

Location .................

INAA

WC

R

ICAP-MS

Ash

D

EDXRF

Ash

R

EDXRF

WC

R

DCAES

Ash

R

ICAP-MS

Ash

D

DCAES

Ash

R

INAA

WC

R

ICAP-MS

Ash

D

DCAES

Ash

R

INAA

WC

R

ICAP-MS

Ash

D

DCAES

Ash

R

UF PC-1-1 .......... 18.1 15.0 15.1 27 <9 1.82 <14 <20 7.2 10 1.98 1.47 <1.4

UF PC-1-2 .......... 18.2 17.3 18.4 46 10 1.96 <14 <18 7.4 <4 1.94 1.51 <1.4

UF PC-1-3 .......... 18.7 18.4 17.5 48 <9 2.01 <14 8.0 7.8 5.0 2.00 1.65 <1.4

AVG PC-1........... 18.3 17.6 17.0 40 (10) 1.93 — (8.0) 7.5 8 1.97 1.55 —

WY PC-2-1......... 9.07 8.0 6.1 18 6.3 .918 <9 <13 3.7 <6 .968 .71 <.8

WY PC-2-2......... 9.5 7.6 4.2 21 10 .867 <9 <11 3.4 <6 .988 .65 <.8

WY PC-2-3......... 9.6 8.5 <3 35 9.3 .994 <9 <9 3.7 <6 .977 .76 <.8

AVG PC-2........... 9.4 8.0 5.2 25 9 .926 — — 3.6 — .978 .71 —

IL PC-3-1............ 12.5 13 6.8 23 <32 1.4 <17 <10 5.5 <11 1.19 1.1 <1.6

IL PC-3-2............ 12.5 13 8.4 39 <32 1.5 <17 <8 5.7 <11 1.18 1.1 <1.6

IL PC-3-3............ 12.8 11 6.5 64 28 1.2 <17 <11 4.5 6.5 1.22 .86 <1.6

AVG PC-3........... 12.6 12 7.2 40 (28) 1.3 — — 5.2 (6.5) 1.20 1.0 —

PITT PC-4-1....... 11.5 10.7 7.4 19 <18 1.18 <10 <12 4.7 4.3 1.10 .91 <.9

PITT PC-4-2....... 11.5 10.3 9.94 25 <18 1.11 <10 <8 4.3 4.2 1.09 .75 <.9

PITT PC-4-3....... 11.1 9.75 9.57 6 <18 1.07 <10 <10 4.0 3.2 1.09 .81 <.9

AVG PC-4........... 11.3 10.3 9.0 17 — 1.12 — — 4.3 3.9 1.10 .83 —

POC PC-5-1........ 11.6 12.0 {5.30} 4 12 1.38 <6 <18 5.51 5.3 1.23 1.05 .74

POC PC-5-2........ 11.8 11.2 8.59 19 10 1.29 <6 <16 4.9 6.9 1.21 .965 .69

POC PC-5-3........ 11.5 10.9 8.90 8 14 1.20 <6 <14 4.7 5.8 1.21 .965 .85

AVG PC-5........... 11.6 11.3 7.6 10 12 1.29 — — 5.1 6.0 1.22 .995 .76

UT PC-6-1.......... 4.88 4.5 — 20 7.4 .524 .44 <3 2.1 2.9 .517 .36 .37

UT PC-6-2.......... 4.67 4.83 — 13 7.4 .557 .42 2.5 2.1 <7 .500 .37 .38

UT PC-6-3.......... 4.84 4.69 — 12 6.0 .557 .39 1.6 2.1 <7 .507 .39 .36

AVG PC-6........... 4.81 4.7 — 15 6.9 .546 .42 2.0 2.1 (2.9) .508 .37 .37

WV PC-7-1......... 36.0 35.7 28.2 64 25 3.86 1.94 12.4 15 19 3.56 2.72 1.7

WV PC-7-2......... 35.2 38.4 31.7 54 27 4.28 1.79 11.0 16 19 3.50 2.95 1.7

WV PC-7-3......... 36.1 37.1 29.9 48 25 4.04 <2 12.4 14 18 3.51 2.74 <.6

AVG PC-7........... 35.8 37.1 29.9 55 26 4.06 1.87 11.9 15 19 3.52 2.80 1.7

ND PC-8-1.......... 4.34 4.2 — 21 <6 .41 <.7 <3 1.5 <3 .420 .27 <.3

ND PC-8-2.......... 4.33 4.1 — 19 <6 .47 <.7 2.1 1.6 <3 .419 .26 <.3

ND PC-8-3.......... 4.68 4.0 — 17 <6 .42 <.7 2.5 1.4 <14 .388 .24 .47

AVG PC-8........... 4.45 4.1 — 19 — .43 — 2.3 1.5 — .409 .26 (.47)
94 CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Eu (ppm) Tb (ppm) Yb (ppm) Hf (ppm) Ta (ppm) W (ppm)

Technique ..........

Mat. analyzed ....

Location.............

INAA

WC

R

ICAP-MS

Ash

D

DCAES

Ash

R

INAA

WC

R

ICAP-MS

Ash

D

INAA

WC

R

ICAP-MS

Ash

D

DCAES

Ash

R

INAA

WC

R

ICAP-MS

Ash

D

INAA

WC

R

ICAP-MS

Ash

D

INAA

WC

R

ICAP-MS

Ash

D

UF PC-1-1....... 0.389 0.32 <0.3 0.275 0.22 0.91 0.74 0.84 0.647 0.81 0.207 0.22 1.00 1.1

UF PC-1-2....... .399 .35 <.3 .252 .24 .84 .78 .82 .660 .80 .224 .19 1.09 1.3

UF PC-1-3....... .406 .34 <.3 .260 .24 .90 .92 .86 .67 .92 .227 .18 1.09 1.3

AVG PC-1 ....... .398 .34 — .262 .23 .88 .81 .84 .66 .85 .219 .20 1.06 1.2

WY PC-2-1 ..... .201 .15 <.2 .122 .10 .42 .32 .23 .621 .65 .141 .13 .38 .48

WY PC-2-2 ..... .199 .16 <.2 .122 .10 .443 .36 .30 .622 .68 .155 .12 .36 .41

WY PC-2-3 ..... .195 .19 <.2 .115 .11 .40 .44 .35 .560 .71 .142 .10 .40 .49

AVG PC-2 ....... .198 .17 — .120 .10 .42 .37 .29 .601 .68 .146 .12 .38 .46

IL PC-3-1 ........ .229 .23 <.4 .147 .14 .51 .52 .63 .54 .92 .188 .19 1.53 1.9

IL PC-3-2 ........ .222 .19 <.4 .131 .15 .511 .52 .58 .532 .71 .197 .18 1.52 2.1

IL PC-3-3 ........ .227 .18 <.4 .136 .12 .551 .52 .68 .578 .68 .189 .16 1.50 1.7

AVG PC-3 ....... .226 .20 — .138 .14 .52 .52 .61 .55 .76 .191 .18 1.52 1.62

PITT PC-4-1.... .221 .17 <.3 .133 .11 .478 .44 .63 .518 .63 .168 .13 .79 .89

PITT PC-4-2.... .214 .18 <.3 .131 .12 .463 .42 .51 .49 .61 .163 .14 .80 .86

PITT PC-4-3.... .208 .17 <.3 .132 .11 .468 .43 .48 .500 .60 .168 .13 .76 .82

AVG PC-4 ....... .214 .17 — .132 .11 .470 .43 .54 .50 .61 .166 .13 .78 .86

POC PC-5-1 .... .243 .22 <.3 .158 .17 .555 .578 .46 .441 .58 .117 .13 .84 1.2

POC PC-5-2 .... .241 .21 <.2 .173 .16 .56 .572 .47 .429 .58 .108 .11 .91 1.1

POC PC-5-3 .... .218 .21 <.2 .169 .15 .545 .567 .42 .444 .53 .123 .10 .77 1.0

AVG PC-5 ....... .234 .21 — .167 .16 .555 .572 .45 .438 .56 .116 .11 .84 1.1

UT PC-6-1....... .100 .078 <.2 .065 .051 .204 .19 .22 .478 .51 .060 .055 .42 .51

UT PC-6-2....... .098 .087 <.1 .054 .060 .198 .20 .20 .499 .60 .046 .060 .40 .51

UT PC-6-3....... .098 .087 .11 .054 .055 .211 .21 .21 .458 .56 .038 .056 .38 .51

AVG PC-6 ....... .099 .084 (.11) .058 .055 .204 .20 .21 .478 .56 .048 .046 .42 .51

WV PC-7-1 ..... .674 .60 .47 .408 .37 1.69 1.4 1.8 1.88 2.3 .675 .62 1.33 1.6

WV PC-7-2 ..... .651 .62 .48 .390 .43 1.61 1.7 1.4 1.80 2.3 .617 .68 1.19 {18}

WV PC-7-3 ..... .697 .62 .89 .402 .39 1.52 1.5 1.4 1.80 2.3 .630 .56 2.53 1.7

AVG PC-7 ....... .674 .61 .61 .400 .40 1.61 1.5 1.5 1.83 2.3 .641 .583 1.68 1.6

ND PC-8-1 ...... .079 .053 <.2 .052 .053 .317 .21 .22 .342 .41 .095 <0.1 .38 .34

ND PC-8-2 ...... .077 .052 <.2 .052 .053 .298 .25 .19 .341 .45 .088 <0.1 .25 .38

ND PC-8-3 ...... .087 .058 <.2 .063 .058 .245 .23 .20 .340 .41 .095 <0.1 .43 .36

AVG PC-8 ....... .081 .054 — .056 .055 .287 .23 .20 .341 .42 .092 — .35 .36
APPENDIX 1 95

Appendix 1. Comparison of the concentrations of 51 elements determined by multiple analytical techniques in 8 Argonne Premium Coal

samples—Continued.

[Analyses of splits for each sample are followed by an average. —, no data. See definitions on p. 77] 

Pb (ppm) Bi (ppm) Th (ppm) U (ppm)

Technique....................

Material analyzed........

Location ......................

GFAAS

Ash

R

ICAP-MS

Ash

D

DCAES

Ash

R

DCAES

WC

R

ICAP-MS

Ash

D

DCAES

Ash

R

INAA

WC

R

ICAP-AES

Ash

D

INAA

WC

R

ICAP-MS

Ash

D

UF PC-1-1 .............. 7.8 7.7 10 8.0 0.12 <1.4 2.59 2.8 0.81 1.2

UF PC-1-2 .............. 7.4 7.7 10 10 .12 <1.4 2.64 2.8 .81 1.2

UF PC-1-3 .............. 6.9 7.4 11 6.0 .11 <1.4 1.55 2.6 .86 1.1

AVG PC-1............... 7.4 7.6 10 8 .12 — 2.26 2.7 .83 1.2

WY PC-2-1............. 3.1 1.6 2.6 <2 .055 <.9 1.56 1.4 .55 .65

WY PC-2-2............. 3.0 1.6 4.1 <2 .055 <.9 1.58 1.6 .54 .62

WY PC-2-3............. 2.7 1.5 3.5 <2 .049 <.9 2.01 1.3 .52 .63

AVG PC-2............... 2.9 1.6 3.4 — .053 — 1.71 1.4 .54 .63

IL PC-3-1................ 6.8 8.6 14 9 .089 <1.7 1.95 2.4 4.46 6.84

IL PC-3-2................ 6.3 8.7 13 8 .087 <1.7 1.95 2.1 4.06 6.58

IL PC-3-3................ 6.3 8.1 14 6 <.08 <1.7 1.99 1.9 4.28 5.95

AVG PC-3............... 6.5 8.5 14 8 .088 — 1.96 2.2 4.27 6.46

PITT PC-4-1........... 2.9 3.8 7.3 4 .12 2.0 1.53 1.8 .36 .60

PITT PC-4-2........... 2.9 4.0 6.9 3 .12 1.5 1.46 1.4 .37 .56

PITT PC-4-3........... 2.9 3.7 7.7 5 .11 <.9 1.44 1.6 .45 .55

AVG PC-4............... 2.9 3.8 7.3 4 .12 1.8 1.48 1.6 .39 .57

POC PC-5-1............ 2.5 1.8 12 5 .049 <.5 1.19 1.2 .47 .646

POC PC-5-2............ 2.4 1.7 8.5 4 .052 <.5 1.12 1.1 .51 .615

POC PC-5-3............ 2.4 1.6 12 5 .053 <.5 1.17 1.2 .55 .631

AVG PC-5............... 2.4 1.7 11 5 .052 — 1.16 1.2 .51 .631

UT PC-6-1.............. 1.6 1.4 2.1 — .035 <1 .609 .60 .76 .851

UT PC-6-2.............. 1.6 1.5 1.7 — .036 <1 .614 .60 .70 .823

UT PC-6-3.............. — 1.5 2.0 — .035 <1 .622 .55 .76 .819

AVG PC-6............... 1.6 1.5 1.9 — .035 — .615 .58 .74 .852

WV PC-7-1............. 12 12 18 — .23 <5 6.49 6.2 1.67 2.17

WV PC-7-2............. 12 12 16 — .23 <5 6.26 6.4 1.60 2.21

WV PC-7-3............. 12 12 13 — .23 <5 6.49 6.6 1.64 2.10

AVG PC-7............... 12 12 16 — .23 — 6.41 6.4 1.64 2.16

ND PC-8-1.............. 1.5 1.9 2.7 — <.05 <2 1.06 {.6} .52 .42

ND PC-8-2.............. 1.5 .84 2.1 — <.05 <2 1.03 {.8} .46 .47

ND PC-8-3.............. 1.5 1.5 3.0 — <.05 <2 1.11 {.7} <.2 .46

AVG PC-8............... 1.5 1.6 2.6 — — — 1.07 .7 .49 .45
Appendix 2. Statistical parameters for the data in appendix 1.

Concentrations of 51 elements in 8 Argonne Premium Coals were determined by multiple analytical techniques (appendix 1). Statistical parameters for non-outlier concentrations determined by high-precision (HP) techniques and for concentrations (including

outliers) determined by all techniques (HP and less precise techniques) are listed in this

appendix in separate columns for each element; only one column is needed for elements

for which all values were determined by HP techniques and no concentrations were outliers (Li, Cs, Tb, Hf, Ta, U). Concentrations of major elements (Si, Al, Fe, Mg, Ca, Na, K,

Ti, P, Mn) are in weight percent (wt. %); concentrations of trace elements are in parts per

million (ppm).

The mean values in HP columns are recommended values if there is no box for that

sample in that column. They are concentrations determined from the arithmetic mean of

the HP values, except values that were excluded in tables 5 and 6 of the paper (this volume) by Palmer and Klizas. The mean concentration is a recommended value if all the

following conditions are met:

(1) the number of determinations (n) is greater than 3, 

(2) the relative standard deviation (Rel Std Dev) is less than 5 percent for major elements present in concentrations greater than 0.1 percent or is less than 10 percent

for trace elements or for major elements present in concentrations less than 0.1

percent (see paper by Palmer and Klizas), and

(3) the deviation of the arithmetic mean and the geometric mean (Dev of Means) is

less than 1 percent.

If any of these conditions is not met (as indicated by a box around the value), the mean is

reported as an average value in tables 5 and 6 of the paper by Palmer and Klizas.

The standard deviation represents the error in the recommended values and was used

to determine significant figures. The kurtosis and skewness are also included. ERR indicates that there were insufficient data to calculate the statistical parameter. 
APPENDIX 2 97

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Si HP Si All Al HP Al All Fe HP Fe All Mg HP Mg All Ca HP Ca All

UF PC-1

n ....................................... 5 11 8 14 11 17 8 14 8 14

Mean (wt. %) ................... 2.63 3.0 1.58 1.8 1.8 1.8 .080 .10 .42 .5

Standard Dev (wt. %)....... .081 .43 .046 .38 .11 .34 .0023 .028 .023 .10

Rel Std Dev (%)............... 3.09 14.6 2.94 20.4 5.93 18.6 2.93 28.8 5.48 21.0

Geometric Mean (wt. %) . 2.62 2.9 1.57 1.8 1.8 1.8 .079 .09 .42 .5

Dev of Means (%)............ .04 .89 .04 1.76 .16 1.39 .04 3.33 .13 1.98

Kurtosis............................ .641 2.68 -.753 .508 .0521 8.44 .900 .797 -2.17 -1.30

Skewness.......................... -1.05 1.53 -.277 1.22 -.304 2.32 -.904 1.42 .590 .573

WY PC-2

n ....................................... 5 11 8 14 11 17 8 14 8 14

Mean (wt. %) ................... 1.1 1.1 .68 .6 .35 .33 .23 .25 1.12 1.1

Standard Dev (wt. %)....... .12 .27 .034 .10 .025 .048 .028 .066 .087 .13

Rel Std Dev (%)............... 11.0 24.9 4.94 17.1 6.99 14.8 12.3 26.5 7.70 11.6

Geometric Mean (wt. %) . 1.1 1.0 .68 .6 .35 .32 .23 .24 1.12 1.1

Dev of Means (%)............ .49 3.51 .11 1.50 .23 1.22 .67 2.91 .27 .61

Kurtosis............................ -2.93 .766 -.973 -.959 -1.00 1.70 -1.37 .321 -.124 -.147

Skewness.......................... .153 -.720 -.567 -.680 -.255 -1.3 -.033 1.22 -.840 .735

IL PC-3

n ....................................... 4 11 7 14 11 17 6 14 8 14

Mean (wt. %) ................... 3.05 3.2 1.24 1.6 2.6 2.5 .075 .09 .93 1.2

Standard Dev (wt. %)....... .041 .43 .035 .38 .16 .28 .0037 .016 .039 .44

Rel Std Dev (%)............... 1.35 13.3 2.79 24.3 6.16 11.0 4.94 17.6 4.16 35.4

Geometric Mean (wt. %) . 3.04 3.2 1.24 1.5 2.6 2.5 .075 .09 .93 1.2

Dev of Means (%)............ .01 .76 .03 2.72 .18 .60 .11 1.43 .08 5.37

Kurtosis............................ 1.79 -.0299 -1.29 -2.08 .782 -.195 3.97 -.966 -1.40 -.951

Skewness.......................... .713 1.05 .235 .337 -1.32 -.588 -1.89 .393 -.532 .920

PITT PC-4

n ....................................... 5 11 7 14 11 17 6 14 8 14

Mean (wt. %) ................... 1.86 2.2 .99 1.4 1.33 1.4 .036 .05 .197 .26

Standard Dev (wt. %)....... .088 .46 .011 .54 .071 .29 .0027 .017 .0099 .093

Rel Std Dev (%)............... 4.72 20.7 1.14 39.7 5.33 20.7 7.71 35.9 5.02 35.7

Geometric Mean (wt. %) . 1.86 2.2 .99 1.3 1.33 1.4 .035 .04 .197 .25

Dev of Means (%)............ .09 1.83 .01 6.96 .13 1.94 .25 5.13 .11 5.23

Kurtosis............................ -3.16 -.951 -2.26 -1.61 .191 .218 -3.33 2.30 -1.21 .330

Skewness.......................... .638 .872 -.0177 .732 -.0179 .827 -5.7 ́10-15 1.55 -.31 3 1.24

POC PC-5

n ....................................... 4 10 7 14 11 17 8 14 8 14

Mean (wt. %) ................... .76 .9 .552 .7 .51 .54 .058 .07 .452 .6

Standard Dev (wt. %)....... .038 .10 .0062 .13 .015 .085 .0055 .021 .0069 .15

Rel Std Dev (%)............... 4.95 12.1 1.12 19.9 2.98 15.8 9.37 28.2 1.52 27.7

Geometric Mean (wt. %) . .76 .8 .552 .6 .51 .53 .058 .07 .452 .5

Dev of Means (%)............ .09 .65 .01 1.71 .04 1.01 .36 3.43 .01 3.08

Kurtosis............................ .257 -1.39 -1.05 -.511 -.33 5.51 -.225 -.416 .264 1.41

Skewness.......................... .358 .397 .812 .944 -.892 2.26 1.29 .956 -.0133 1.47

UT PC-6

n ....................................... 4 7 6 9 9 12 6 9 5 9

Mean (wt. %) ................... .91 .89 .37 .35 .30 .28 .033 .036 .41 .36

Standard Dev (wt. %)....... .027 .068 .020 .035 .016 .034 .0074 .0071 .013 .063

Rel Std Dev (%)............... 2.97 7.66 5.31 10.1 5.37 12.0 22.5 20.0 3.16 17.3

Geometric Mean (wt. %) . .91 .89 .37 .35 .30 .28 .032 .035 .41 .36

Dev of Means (%)............ .03 .28 .12 .47 .13 .74 1.77 1.72 .04 1.43

Kurtosis............................ -2.57 5.17 -1.89 -1.01 -1.19 .994 5.57 -1.04 -3.07 -1.98

Skewness.......................... .257 -2.20 .045 -.351 .509 -1.14 2.33 -.820 -.293 -.435

WV PC-7

n ....................................... 4 7 7 10 10 13 6 10 6 10

Mean (wt. %) ................... 5.0 5.1 3.16 3.4 .39 .39 .090 .09 .058 .06

Standard Dev (wt. %)....... .22 .48 .024 .44 .014 .024 .0057 .014 .0017 .013

Rel Std Dev (%)............... 4.32 9.51 .75 12.9 3.52 6.21 6.39 15.9 2.89 19.6

Geometric Mean (wt. %) . 5.0 5.1 3.16 3.4 .39 .39 .090 .09 .058 .06

Dev of Means (%)............ .07 .39 0 .68 .06 .18 .17 .99 .03 1.46

Kurtosis............................ 1.50 .274 -.861 1.64 -1.30 1.69 -1.67 5.40 2.50 4.10

Skewness.......................... 1.19 -.105 -.802 1.78 .242 .647 -.470 2.14 1.15 2.14

ND PC-8

n ....................................... 3 7 6 10 10 13 7 10 7 10

Mean (wt. %) ................... .67 .65 .400 .35 .49 .46 .38 .42 1.49 1.4

Standard Dev (wt. %)....... 0 .068 .0036 .088 .042 .067 .029 .068 .061 .12

Rel Std Dev (%)............... 0 10.4 .90 24.7 8.61 14.6 7.73 16.2 4.07 8.06

Geometric Mean (wt. %) . .67 .65 .400 .34 .49 .46 .38 .42 1.49 1.4

Dev of Means (%)............ 0 .47 0 3.40 .32 1.06 .26 1.15 .07 .31

Kurtosis............................ ERR 1.90 -1.94 -.534 -.793 .404 -2.14 -1.37 -2.33 .515

Skewness.......................... ERR --.0112 -.202 -1.06 .975 -.533 -.0612 -1.07 -.114 -.935
98 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Na HP Na All K HP K All Ti HP Ti All P HP P All Mn HP Mn All

UF PC-1

n ...................................... 9 14 11 14 8 14 6 8 6 12

Mean (wt. %) .................. .033 .035 .28 .28 .078 .08 .007 .007 .0043 .0048

Standard Dev (wt. %) ..... .0010 .0055 .013 .015 .0032 .017 .0011 .0012 .00014 .00067

Rel Std Dev (%).............. 3.08 15.6 4.53 5.20 4.08 21.8 16.3 18.1 3.24 13.9

Geometric Mean (wt. %) .033 .035 .28 .28 .077 .08 .007 .006 .0042 .0048

Dev of Means (%)........... .04 1.03 .09 .13 .07 2.62 1.12 1.42 .04 .87

Kurtosis........................... -1.74 .810 -.111 -.276 .293 .893 -3.03 -1.60 -2.30 -1.42

Skewness......................... -.733 1.41 -.038 .169 -.614 -.547 .115 .409 -7.44 ́10-16 .471

WY PC-2

n ...................................... 11 14 9 14 8 14 6 14 6 12

Mean (wt. %) .................. .11 .12 .030 .031 .053 .047 .024 .026 .0020 .0022

Standard Dev (wt. %) ..... .012 .016 .0044 .0039 .0033 .0081 .0023 .0043 7.52 ́10-5 .00084

Rel Std Dev (%).............. 10.2 13.9 14.6 12.8 6.27 17.2 9.72 16.6 3.80 39.0

Geometric Mean (wt. %) .11 .12 .030 .030 .053 .047 .024 .026 .0020 .0020

Dev of Means (%)........... .55 .75 .89 .73 .17 1.55 .41 1.32 .06 6.54

Kurtosis........................... 4.60 4.02 -.489 -.598 -1.75 -.132 -2.00 -1.23 -.104 2.40

Skewness......................... -2.19 -1.45 1.05 .753 -.420 -.815 -.568 .0122 .313 1.34

IL PC-3

n ...................................... 10 14 11 14 6 14 3 8 6 12

Mean (wt. %) .................. .10 .11 .20 .22 .070 .07 .0059 .005 .0081 .011

Standard Dev (wt. %) ..... .010 .022 .013 .028 .0028 .012 .00012 .0012 .00065 .0033

Rel Std Dev (%).............. 9.67 19.6 6.20 12.9 4.04 16.9 1.95 25.1 8.03 30.9

Geometric Mean (wt. %) .10 .11 .20 .21 .069 .07 .0059 .004 .0081 .010

Dev of Means (%)........... .39 1.64 .17 .71 .07 1.28 .01 2.83 .26 4.07

Kurtosis........................... 4.46 .00612 .170 1.00 4.51 1.23 ERR -1.67 -.3 -.453

Skewness......................... 1.92 1.14 .811 1.30 -1.99 .807 -1.73 .278 .857 .949

PITT PC-4

n ...................................... 9 14 11 14 8 14 6 11 6 12

Mean (wt. %) .................. .033 .034 .111 .115 .055 .06 .010 .009 .0019 .0024

Standard Dev (wt. %) ..... .0013 .0028 .0025 .0091 .0040 .016 .0020 .0014 .00019 .00082

Rel Std Dev (%).............. 3.79 8.33 2.21 7.90 7.35 25.0 20.8 15.3 9.99 34.8

Geometric Mean (wt. %) .033 .034 .111 .115 .055 .06 .009 .009 .0019 .0022

Dev of Means (%)........... .06 .31 .02 .27 .24 2.53 2.16 1.24 .42 5.02

Kurtosis........................... -1.02 .366 -1.14 3.67 -1.51 .671 1.30 2.61 -2.69 -.156

Skewness......................... -.760 .845 .865 2.00 -.177 .145 -1.28 -1.24 -2.3 ́10-15 1.10

POC PC-5

n ...................................... 11 14 9 14 8 14 5 8 6 12

Mean (wt. %) .................. .079 .09 .031 .031 .039 .05 .00222 .0021 .0017 .0019

Standard Dev (wt. %) ..... .0047 .022 .0039 .0039 .0022 .0202 8.4 ́10-5 .00013 .00013 .00038

Rel Std Dev (%).............. 5.92 24.4 12.9 12.5 5.65 44.1 3.77 6.09 7.74 19.3

Geometric Mean (wt. %) .079 .09 .030 .031 .039 .04 .00220 .0021 .0017 .00191

Dev of Means (%)........... .17 2.40 .72 .72 .13 7.84 .06 .16 .25 1.64

Kurtosis........................... 1.04 .317 -1.30 -.789 4.49 .287 -.612 -1.92 -2.25 -1.24

Skewness......................... -1.34 1.41 .592 .438 2.03 1.33 -.512 .105 .326 .711

UT PC-6

n ...................................... 9 12 5 10 5 9 2 75 8

Mean (wt. %) .................. .135 .12 .025 .021 .023 .021 .00095 .0008 .000416 .00049

Standard Dev (wt. %) ..... .0089 .030 .0043 .0056 0 .0022 3.5 ́10-5 .00014 8.94 ́10-6 .000127

Rel Std Dev (%).............. 6.64 25.3 17.0 26.1 0 10.5 3.74 16.9 2.15 26.0

Geometric Mean (wt. %) .134 .11 .025 .021 .023 .021 .00095 .0008 .000416 .00048

Dev of Means (%)........... .19 3.82 1.34 3.29 0 .51 .04 1.32 .02 2.57

Kurtosis........................... -1.33 .0315 3.15 -1.59 ERR -1.61 ERR -.436 .312 1.05

Skewness......................... .640 -1.19 -1.68 -.0162 ERR -.621 ERR -.465 1.26 1.56

WV PC-7

n ...................................... 8 13 10 13 7 10 3 8 6 9

Mean (wt. %) .................. .0348 .037 .49 .46 .25 .22 .0083 .0091 .00147 .0016

Standard Dev (wt. %) ..... .00085 .00499 .022 .064 .015 .036 .00081 .0032 8.16 ́10-5 .00030

Rel Std Dev (%).............. 2.45 13.4 4.50 13.9 6.27 15.8 9.77 35.5 5.57 18.5

Geometric Mean (wt. %) .0348 .037 .49 .46 .25 .22 .0083 .0088 .0015 .0016

Dev of Means (%)........... .03 .73 .09 1.01 .17 1.22 .33 4.08 .13 1.38

Kurtosis........................... 2.95 3.58 .0548 .345 -1.10 -1.37 ERR 7.15 -.3 1.69

Skewness......................... -1.07 2.10 -.0434 -1.24 -.473 -.623 -1.62 2.63 .857 1.43

ND PC-8

n ...................................... 10 11 5 12 6 10 6 14 6 10

Mean (wt. %) .................. .50 .47 .034 .03 .0192 .019 .012 .014 .0081 .009

Standard Dev (wt. %) ..... .027 .079 .0063 .010 .00083 .0012 0 .0044 .00016 .0011

Rel Std Dev (%).............. 5.40 16.6 18.6 34.5 4.35 6.20 0 32.7 1.97 12.3

Geometric Mean (wt. %) .50 .47 .034 .03 .0192 .019 .012 .013 .0081 .009

Dev of Means (%)........... .13 1.75 1.31 7.32 .08 .18 0 4.96 .02 .67

Kurtosis........................... -.720 8.14 1.05 .646 -2.27 -1.05 ERR -.961 -1.31 -.948

Skewness......................... .305 -2.69 1.19 -.597 -.297 -.559 ERR .625 .0405 .497
APPENDIX 2 99

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Li HP Be HP Be All B HP B All Sc HP Sc All V HP V All

UF PC-1

n...................................... 6 6 9 3 6 6 9 6 12

Mean (ppm).................... 14.8 1.5 1.5 38 34 3.99 3.4 26.5 28

Standard Dev (ppm) ....... 0 0 .1 9.4 12 .094 .99 .55 9.6

Rel Std Dev (%) ............. 0 0 6.82 24.5 35.3 2.37 29.4 2.07 34.9

Geometric Mean (ppm).. 14.8 1.5 1.5 38 32 3.99 3.2 26.5 26

Dev of Means (%) .......... 0 0 .23 1.92 5.71 .02 5.19 .02 5.99

Kurtosis .......................... -3.33 ERR 9.00 ERR -1.67 -.384 -.302 -3.33 -.301

Skewness ........................ 1.37 ERR -3.00 1.37 .127 .863 -1.142 0 .448

WY PC-2

n...................................... 6 3 9 3 6 6 9 6 12

Mean (ppm).................... 4.0 .25 .22 96 83 1.66 1.5 14 13

Standard Dev (ppm) ....... .11 .01 .056 13 17 .034 .23 .00 2.8

Rel Std Dev (%) ............. 2.85 4.0 25.9 13.7 21.5 2.05 14.6 0 22.1

Geometric Mean (ppm).. 4.0 .250 .21 96 82 1.66 1.5 14 12

Dev of Means (%) .......... .03 .000534 3.53 .62 1.74 .02 1.17 0 2.59

Kurtosis .......................... -2.14 ERR -1.68 ERR .0757 -1.78 4.54 ERR -.344

Skewness ........................ .357 1.46 ́10-17 -.817 .966 .724 -.479 -2.09 ERR -.624

IL PC-3

n...................................... 6 3 9 3 6 6 9 6 12

Mean (ppm).................... 7.8 .76 .8 160 140 2.65 2.6 35 36

Standard Dev (ppm) ....... .19 .017 .16 2.9 23 .094 .11 3.3 11

Rel Std Dev (%) ............. 2.41 2.3 19.6 1.80 16.5 3.55 4.04 9.48 30.7

Geometric Mean (ppm).. 7.8 .7599 .8 160 140 2.64 2.6 34 35

Dev of Means (%) .......... .02 .000172 1.62 .01 1.17 .05 .07 .37 4.19

Kurtosis .......................... -.446 ERR .109 ERR -2.43 -2.01 -1.39 -2.08 .239

Skewness ........................ -.668 1.73 .949 -1.73 -.272 .577 .429 .309 .837

PITT PC-4

n...................................... 6 3 9 3 6 6 9 6 12

Mean (ppm).................... 8.6 .77 .9 47.8 50 2.53 2.3 16 17

Standard Dev (ppm) ....... .36 .012 .21 .95 2.4 .055 .36 1.1 4.7

Rel Std Dev (%) ............. 4.17 1.51 23.5 1.99 4.84 2.18 15.6 6.85 27.42

Geometric Mean (ppm).. 8.6 .77 .9 47.8 50 2.53 2.3 16 17

Dev of Means (%) .......... .07 .01 2.28 .01 .10 .02 1.20 .20 3.15

Kurtosis .......................... .521 ERR -1.43 ERR -1.35 -1.36 -1.03 -3.33 .710

Skewness ........................ .673 1.73 .911 .158 .613 .583 -.962 0 1.17

POC PC-5

n...................................... 6 6 9 3 6 6 9 6 12

Mean (ppm).................... 5.6 .80 .76 13.1 15 1.78 1.6 11.5 12

Standard Dev (ppm) ....... .27 0 .077 .64 2.6 .023 .21 .55 4.4

Rel Std Dev (%) ............. 4.78 0 10.2 4.86 16.8 1.32 13.0 4.76 36.1

Geometric Mean (ppm).. 5.6 .80 .75 13.1 15 1.78 1.6 11.5 11

Dev of Means (%) .......... .10 0 .52 .08 1.17 .01 .83 .09 6.08

Kurtosis .......................... -1.88 -3.33 3.24 ERR -1.34 -2.41 -.787 -3.33 .210

Skewness ........................ -.960 1.37 -1.89 1.73 .487 -.245 -1.07 0 .740

UT PC-6

n...................................... 5 2 10 3 3 6 9 58

Mean (ppm).................... 5.3 .125 .16 127 127 .78 .75 4.3 4.05

Standard Dev (ppm) ....... .25 .0071 .039 5.2 5.2 .037 .060 .27 .38

Rel Std Dev (%) ............. 4.72 5.66 24.5 4.09 4.09 4.75 8.04 6.27 9.43

Geometric Mean (ppm).. 5.3 .125 .16 127 127 .78 .75 4.27 4.03

Dev of Means (%) .......... .09 .08 2.45 .05 .05 .09 .30 .16 .39

Kurtosis .......................... -3.33 ERR .312 ERR ERR -1.52 -.00338 -2.41 -1.55

Skewness ........................ -.609 ERR 1.19 1.73 1.73 -.145 -.618 -.166 .185

WV PC-7

n...................................... 6 6 12 3 6 6 9 69

Mean (ppm).................... 28 2.0 2.3 56 56 7.5 7.13 43.3 39

Standard Dev (ppm) ....... 1.0 .11 .51 20 24 .14 .62 .82 6.1

Rel Std Dev (%) ............. 3.70 5.48 22.0 35.9 43.1 1.84 8.69 1.88 15.4

Geometric Mean (ppm).. 28 2.0 2.3 50 50 7.5 7.11 43.3 39

Dev of Means (%) .......... .06 .13 2.10 4.25 8.02 .01 .36 .01 1.17

Kurtosis .......................... -3.33 -3.33 -1.53 ERR -.851 -1.95 .154 6.00 -.784

Skewness ........................ -7.7 ́10-15 4.76 ́10-18 .746 1.09 .686 .474 -1.26 2.449 -1.03

ND PC-8

n...................................... 6 2 10 3 6 3 9 69

Mean (ppm).................... 2.69 .175 .22 79 73 .80 .83 3.7 3.6

Standard Dev (ppm) ....... .078 .0071 .054 1.1 12 .049 .064 .21 .18

Rel Std Dev (%) ............. 2.88 4.04 24.2 1.38 17.0 6.07 7.71 5.80 4.97

Geometric Mean (ppm).. 2.69 .175 .22 79 72 .20 .83 3.7 3.6

Dev of Means (%) .......... .03 .04 2.42 .01 1.52 .20 .26 .14 .11

Kurtosis .......................... 6.00 ERR .0493 ERR 5.65 -.267 -.230 -2.15 -1.19

Skewness ........................ 2.45 ERR 1.09 1.73 -2.36 .231 .314 -.232 .440
100 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Cr HP Cr All Co HP Co All Ni HP Ni All Cu HP Cu All Zn HP Zn All

UF PC-1

n...................................... 12 21 9 15 12 21 9 18 12 18

Mean (ppm) .................... 22 23 5.2 4.8 15 17 18.9 18 20 24

Standard Dev (ppm) ....... 2.6 5.2 .22 .71 2.3 5.0 .98 1.4 1.8 7.0

Rel Std Dev (%).............. 11.9 22.8 4.25 14.7 15.5 28.8 5.18 7.37 9.10 29.0

Geometric Mean (ppm) .. 22 22 5.2 4.8 15 17 18.9 18 20 23

Dev of Means (%) .......... .62 2.20 .08 1.22 1.04 3.62 .12 .26 .36 3.63

Kurtosis .......................... -.530 3.11 3.43 2.20 4.65 .00992 1.49 -.783 2.36 -.238

Skewness ........................ .930 1.53 -1.76 -1.70 1.36 1.03 -.553 -.401 1.30 .997

WY PC-2

n...................................... 11 20 9 12 12 18 9 18 12 15

Mean (ppm) .................... 6.5 6 1.65 1.6 4.7 5.3 13.0 12.7 11.0 14

Standard Dev (ppm) ....... .69 1.3 .088 .21 .50 1.4 .79 3.3 .96 6.2

Rel Std Dev (%).............. 10.6 21.0 5.32 13.7 10.8 25.9 6.08 26.2 8.73 44.8

Geometric Mean (ppm) .. 6.5 6 1.65 1.5 4.6 5.2 12.9 12.2 10.9 13

Dev of Means (%) .......... .47 2.42 .13 1.02 .56 2.70 .16 4.39 .34 7.21

Kurtosis .......................... 3.52 1.55 .326 3.71 -.106 2.58 -1.35 1.22 .343 2.08

Skewness ........................ 1.80 -.209 .112 -1.71 -.583 1.69 -.001 -.836 .593 1.83

IL PC-3

n...................................... 12 21 9 12 11 21 9 18 9 18

Mean (ppm) .................... 36 38 4.4 4.2 19 24 10.1 11 200 190

Standard Dev (ppm) ....... 5.2 7.7 .18 .37 2.5 6.7 .78 1.9 25 60

Rel Std Dev (%).............. 14.6 19.9 4.35 8.87 12.9 28.2 7.74 17.7 12.3 32.3

Geometric Mean (ppm) .. 35 38 4.4 4.2 19 23 10.1 11 200 180

Dev of Means (%) .......... .96 1.76 .08 .39 .78 3.67 .27 1.36 .68 5.37

Kurtosis .......................... -1.38 .582 -.636 1.25 2.74 -.823 -.211 .569 .393 -.0399

Skewness ........................ .584 .992 .867 -1.12 .172 .690 -.411 1.19 .486 .320

PITT PC-4

n...................................... 12 21 9 12 11 20 9 18 11 18

Mean (ppm) .................... 16 16 2.6 2.6 9.2 11 5.8 7 8.3 13

Standard Dev (ppm) ....... 1.6 4.7 .10 .15 .89 2.5 .40 1.6 .83 7.3

Rel Std Dev (%).............. 10.3 28.9 4.03 5.95 9.66 22.8 6.95 24.2 9.91 56.4

Geometric Mean (ppm) .. 16 16 2.6 2.6 9.2 11 5.8 6 8.3 11

Dev of Means (%) .......... .49 4.78 .07 .17 .40 2.34 .21 2.45 .41 12.3

Kurtosis .......................... -.529 .905 .280 -.222 2.16 -.170 -1.77 .548 4.78 1.87

Skewness ........................ .248 .00908 -1.12 -.499 1.30 .826 .221 1.33 1.92 1.63

POC PC-5

n...................................... 12 21 9 12 12 20 9 18 12 15

Mean (ppm) .................... 10 10 3.9 3.6 7.6 8 14 16 5 7

Standard Dev (ppm) ....... 1.4 3.2 .13 .65 .79 1.8 1.9 4.1 1.0 3.9

Rel Std Dev (%).............. 14.1 32.3 3.20 18.1 10.4 21.5 14.1 25.4 19.8 56.5

Geometric Mean (ppm) .. 10 10 3.9 3.5 7.6 8 13 16 5 6

Dev of Means (%) .......... .85 5.38 .05 1.83 .48 2.07 .85 2.76 1.75 12.29

Kurtosis .......................... -.408 .782 -1.45 .553 .160 -.251 -1.75 1.84 .562 .597

Skewness ........................ 1.06 .592 .058 -1.43 .611 .873 .725 1.29 .725 1.48

UT PC-6

n...................................... 8 11 8 11 7 13 5 11 8 8

Mean (ppm) .................... 5.2 5.1 .93 .9 3.4 3.9 4.1 5 6 6

Standard Dev (ppm) ....... .31 .48 .072 .15 .17 .67 .21 2.2 1.1 1.1

Rel Std Dev (%).............. 6.04 9.44 7.74 17.5 4.99 16.92 5.11 45.9 18.8 19.2

Geometric Mean (ppm) .. 5.1 5.0 .93 .8 3.4 3.9 4.1 4 6 6

Dev of Means (%) .......... .16 .45 .27 1.55 .11 1.25 .11 9.49 1.53 1.53

Kurtosis .......................... .874 3.11 -1.18 -1.03 -.638 -.704 -1.96 -.927 -1.51 -1.51

Skewness ........................ -.293 -1.54 -.645 -.705 .169 .872 -.236 .829 .401 .401

WV PC-7

n...................................... 12 15 9 12 12 18 9 15 12 15

Mean (ppm) .................... 40 40 7.8 7.4 16 17 21 22 12 12

Standard Dev (ppm) ....... 3.8 3.7 .34 .79 1.2 2.2 2.1 5.4 1.1 1.5

Rel Std Dev (%).............. 9.51 9.34 4.33 10.7 7.43 12.99 10.0 24.7 9.17 12.52

Geometric Mean (ppm) .. 40 40 7.8 7.4 16 17 21 21 12 12

Dev of Means (%) .......... .41 .40 .08 .57 .26 .75 .44 2.88 .38 .75

Kurtosis .......................... -.935 -.915 .0131 .765 .325 1.46 -.0445 -.300 -1.01 -.5667

Skewness ........................ .516 .330 .805 -1.15 -.0667 1.08 .710 .518 .425 -.412

ND PC-8

n...................................... 12 15 3 9 9 15 8 15 12 15

Mean (ppm) .................... 2.4 2.4 .78 .7 1.5 2 4.2 6 5.2 5.1

Standard Dev (ppm) ....... .21 .19 .021 .15 .37 2.3 .91 2.9 .47 .57

Rel Std Dev (%).............. 8.79 7.84 2.75 20.0 24.3 91.4 22.0 49.6 9.06 11.0

Geometric Mean (ppm) .. 2.4 2.4 .78 .7 1.5 2 4.1 5 5.1 5.1

Dev of Means (%) .......... .35 .28 .02 1.89 2.32 23.46 2.10 10.7 .37 .58

Kurtosis .......................... -1.01 -.482 ERR -1.10 3.38 9.67 -1.55 .0149 -1.28 -.438

Skewness ........................ .437 -.415 1.32 -.181 1.63 2.98 .41 1.08 .215 -.163
APPENDIX 2 101

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Ga HP Ga All Ge HP Ge All As HP As All Se HP Se All Rb HP Rb All

UF PC-1

n ...................................... 3 9 3 9 6 9 6 6 9 12

Mean (ppm) .................... 5.34 7 4.35 3.9 16.7 21 1.9 1.9 21 21

Standard Dev (ppm)........ 1.21 2.3 .053 .48 .59 8.0 .27 .27 1.2 1.2

Rel Std Dev (%).............. 2.26 32.2 1.22 12.4 3.52 37.5 14.1 14.1 5.93 5.98

Geometric Mean (ppm) .. 5.3 7 4.35 3.8 16.6 20 1.9 1.9 21 21

Dev of Means (%)........... .02 4.15 0 .73 .05 5.23 .87 .87 .16 .16

Kurtosis........................... ERR -.260 ERR -.487 -.428 1.57 .556 .556 -.545 -.629

Skewness ........................ -.49 1.16 -1.46 -.698 1.0 1.62 -.368 -.368 -.192 -.031

WY PC-2

n ...................................... 3 9 3 3 6 6 6 6 69

Mean (ppm) .................... 1.9 2.4 .36 .36 3.0 3.0 2.0 2.0 2.7 6

Standard Dev (ppm)........ .12 .70 0 0 .71 .71 .55 .55 .94 5.3

Rel Std Dev (%).............. 6.15 28.6 0 0 23.4 23.4 27.9 27.9 35.3 86.9

Geometric Mean (ppm) .. 1.9 2.4 .36 .36 2.9 2.9 1.9 1.9 2.5 4

Dev of Means (%)........... .12 3.18 0 0 2.59 2.64 3.06 3.06 5.60 40.76

Kurtosis........................... ERR 2.46 ERR ERR -.558 -.558 -1.17 -1.17 -3.16 -1.33

Skewness ........................ 1.508 1.55 -2.45 -2.45 -.523 -.523 .953 .953 .0580 .877

IL PC-3

n ...................................... 3 9 3 9 6 6 6 6 9 12

Mean (ppm) .................... 3.57 5 8.4 9 4.2 4.2 4.2 4.2 15.5 17

Standard Dev (ppm)........ .107 1.6 .27 1.4 .53 .53 .45 .45 .78 2.4

Rel Std Dev (%).............. 2.99 31.4 3.21 16.1 12.6 12.6 10.7 10.7 5.00 14.5

Geometric Mean (ppm) .. 3.57 5 8.4 9 4.2 4.2 4.2 4.2 15.5 16

Dev of Means (%)........... .03 4.03 .03 1.04 .67 .67 .45 .45 .11 .87

Kurtosis........................... ERR .440 ERR 3.82 -2.06 -2.06 3.44 3.44 2.55 1.70

Skewness ........................ -1.71 1.14 -1.293 1.69 -.051 -.051 1.72 1.72 1.40 1.65

PITT PC-4

n ...................................... 3 9 3 7 6 9 6 6 9 12

Mean (ppm) .................... 3.3 4 1.2 1.5 8.0 11 1.6 1.6 8.3 8.2

Standard Dev (ppm)........ .14 1.0 .13 .68 .56 4.6 .15 .15 .82 .71

Rel Std Dev (%).............. 4.27 22.7 10.5 46.7 6.92 41.8 9.64 9.64 9.83 8.64

Geometric Mean (ppm) .. 3.3 4 1.2 1.4 8.0 10 1.6 1.6 8.3 8.2

Dev of Means (%)........... 0 2.43 .37 6.69 .21 7.15 .39 .39 .44 .34

Kurtosis........................... ERR -1.44 ERR 6.59 .001 -.937 1.23 1.23 -1.02 -.484

Skewness ........................ 1.26 -.0535 .87 2.55 -1.15 1.00 -.087 -.087 -.312 .058

POC PC-5

n ...................................... 3 9 3 6 6 9 6 6 69

Mean (ppm) .................... 1.8 2.6 .29 .4 10.1 12 2.7 2.7 2.2 3

Standard Dev (ppm)........ .10 .90 .065 .10 .52 2.8 .30 .30 .20 1.3

Rel Std Dev (%).............. 5.31 34.8 23.2 28.0 5.16 24.2 11.0 11.0 8.76 41.8

Geometric Mean (ppm) .. 1.8 2.5 .28 .4 10.1 11 2.7 2.7 2.2 3

Dev of Means (%)........... .09 5.08 1.76 3.78 .11 2.18 .52 .52 .30 7.17

Kurtosis........................... ERR -.660 ERR -1.81 -2.57 3.74 -1.34 -1.34 4.68 -1.03

Skewness ........................ -.158 .936 1.06 -.415 -.192 1.99 -.173 -.173 2.12 .980

UT PC-6

n ...................................... 3 6 3 3 4 4 6 6 58

Mean (ppm) .................... 1.00 1.1 .23 .23 .45 .45 1.2 1.2 1.02 1.6

Standard Dev (ppm)........ .051 .24 .033 .033 .082 .082 .12 .12 .057 .90

Rel Std Dev (%).............. 5.20 21.1 14.7 14.7 19.7 19.7 10.4 10.4 5.64 55.2

Geometric Mean (ppm) .. .99 1.1 .22 .22 .44 .44 1.2 1.2 1.02 1.5

Dev of Means (%)........... .09 1.74 .71 .71 1.65 1.65 .46 .46 .13 12.68

Kurtosis........................... ERR -.213 ERR ERR 1.23 1.2 -1.97 -1.97 -.628 -1.02

Skewness ........................ 1.73 1.08 -1.55 -1.55 -1.34 -1.34 -.178 -.178 .138 1.00

WV PC-7

n ...................................... 3 6 3 5 6 6 5 6 9 12

Mean (ppm) .................... 9.4 11 1.67 1.5 6.4 6.4 5.6 5.8 36 38

Standard Dev (ppm)........ .44 1.5 .058 .29 .81 .81 .30 .59 6.1 5.7

Rel Std Dev (%).............. 4.68 14.0 3.46 19.9 12.6 12.6 5.30 10.1 16.7 15.2

Geometric Mean (ppm) .. 9.4 10 1.67 1.4 6.4 6.4 5.6 5.8 36 37

Dev of Means (%)........... .07 .79 .04 1.68 .67 .67 .11 .40 1.25 1.13

Kurtosis........................... ERR .605 ERR -2.85 -1.11 -1.11 2.86 2.06 -1.48 -1.26

Skewness ........................ -1.72 .890 -1.73 -.590 -.306 -.306 1.40 1.54 .090 -.469

ND PC-8

n ...................................... 3 6 3 3 4 5 6 6 58

Mean (ppm) .................... 1.16 1.4 .37 .37 2.4 2.0 .59 .59 1.2 2

Standard Dev (ppm)........ .04 .34 .045 .045 .51 .87 .042 .042 .27 1.5

Rel Std Dev (%).............. 3.47 23.4 12.3 12.3 21.4 42.5 7.04 7.04 21.0 69.6

Geometric Mean (ppm) .. 1.16 1.4 .36 .36 2.3 1.8 .59 .59 1.2 2

Dev of Means (%)........... .04 2.25 .51 .51 2.15 11.43 .22 .22 1.92 22.09

Kurtosis........................... ERR -2.14 ERR ERR 3.94 -.154 4.60 4.60 -2.37 -.539

Skewness ........................ 1.73 .486 -.331 -.331 -1.98 -1.17 -1.99 -1.99 -.645 1.01
102 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Sr HP Sr All Y HP Y All Zr HP Zr All Nb HP Nb All Mo HP Mo All

UF PC-1

n ...................................... 12 18 9 12 6 156936

Mean (ppm) .................... 57 59 9 8 26 24 2.5 2.2 2.5 2.0

Standard Dev (ppm)........ 7.6 7.0 1.0 2.3 1.7 7.8 .21 .49 .39 .62

Rel Std Dev (%).............. 13.4 11.9 11.2 28.7 6.67 32.8 8.61 22.2 15.6 30.8

Geometric Mean (ppm)... 56 58 9 8 26 22 2.5 2.1 2.5 1.9

Dev of Means (%)........... 1.13 .90 .56 5.38 .19 7.22 .30 2.61 .77 4.01

Kurtosis........................... 10.8 11.8 .0992 .761 -2.46 .395 -2.15 -.202 ERR -.664

Skewness......................... -3.21 -3.08 .146 -1.11 .0672 -.708 -.232 -.878 1.73 .558

WY PC-2

n ...................................... 9 18 9 12 6 126936

Mean (ppm) .................... 257 240 3.7 3.5 21 19 1.2 1.3 .52 .59

Standard Dev (ppm)........ 6.6 49 .13 .40 2.1 3.1 .25 .28 .021 .087

Rel Std Dev (%).............. 2.55 20.5 3.65 11.4 10.3 16.1 20.5 21.7 4.15 14.7

Geometric Mean (ppm)... 257 230 3.7 3.5 21 19 1.2 1.3 .52 .59

Dev of Means (%)........... .03 2.42 .06 .71 .45 1.38 1.87 2.13 .06 .91

Kurtosis........................... -.362 -.106 2.11 5.55 -1.97 1.65 -1.1 .745 ERR -2.58

Skewness......................... -.848 -1.07 -.152 -2.25 -.179 -1.05 -.453 .339 -.611 .0571

IL PC-3

n ...................................... 12 18 9 12 6 15 5 8 36

Mean (ppm) .................... 32 34 4.1 4.3 23 22 2.2 2.3 6.3 5.7

Standard Dev (ppm)........ 4.5 4.9 .46 .52 3.0 3.8 .23 .43 .92 .83

Rel Std Dev (%).............. 13.9 14.6 11.1 12.1 13.3 17.6 11.2 18.7 14.7 14.43

Geometric Mean (ppm)... 32 33 4.1 4.2 23 21 2.1 2.2 6.3 5.7

Dev of Means (%)........... .81 .96 .58 .71 .71 1.61 .51 1.39 .70 .81

Kurtosis........................... .849 -.592 2.23 1.10 1.65 .0515 -3.09 3.03 ERR 2.56

Skewness......................... 1.43 .847 -.558 -.250 .875 -.634 -.47 1.52 1.20 1.51

PITT PC-4

n ...................................... 12 18 9 12 6 15 6 9 36

Mean (ppm) .................... 64 70 4.4 4.0 19 18 1.8 1.8 .74 .77

Standard Dev (ppm)........ 3.0 11 .45 .72 1.5 4.5 .13 .14 .033 .066

Rel Std Dev (%).............. 4.73 16.1 10.3 17.9 7.65 24.8 7.45 7.63 4.51 8.69

Geometric Mean (ppm)... 64 68 4.3 4.0 19 18 1.8 1.8 .74 .77

Dev of Means (%)........... .10 1.07 .45 1.56 .24 3.16 .23 .25 .07 .31

Kurtosis........................... 1.44 3.43 -.0734 -.295 -2.45 .802 1.3 -.370 ERR -1.75

Skewness......................... .0462 1.95 1.11 -.214 .344 .0791 .440 .631 1.12 .540

POC PC-5

n ...................................... 12 18 9 12 6 15 6 9 36

Mean (ppm) .................... 100 100 6.3 5.9 16.5 17 1.0 1.0 2.7 2.5

Standard Dev (ppm)........ 12 13 .52 .89 .81 7.7 .19 .22 .13 .31

Rel Std Dev (%).............. 11.3 12.8 8.24 15.2 4.92 45.2 19.0 21.1 5.1 12.8

Geometric Mean (ppm)... 100 100 6.3 5.8 16.4 16 1.0 1.0 2.7 2.4

Dev of Means (%)........... .62 .80 .30 1.14 .10 8.66 1.39 1.99 .09 .71

Kurtosis........................... -1.12 -1.12 -1.59 -.703 1.48 1.00 1.37 -1.53 ERR -.927

Skewness......................... -.726 -.394 .341 -.479 -1.49 1.30 1.31 .296 1.48 -.277

UT PC-6

n ...................................... 8 14 5 8 3 9 3 6 36

Mean (ppm) .................... 64 70 2.0 1.9 17.3 15 .57 .54 .42 .45

Standard Dev (ppm)........ 5.2 12 .12 .17 .58 3.4 .070 .062 .023 .063

Rel Std Dev (%).............. 8.16 17.2 6.12 8.67 3.33 21.9 11.8 11.6 5.34 13.9

Geometric Mean (ppm)... 63 70 2.0 1.9 17.3 15 .56 .53 .42 .45

Dev of Means (%)........... .28 1.26 .16 .35 .04 2.48 .50 .52 .10 .79

Kurtosis........................... -1.87 .249 2.00 .994 ERR -.0765 ERR 1.54 ERR -1.11

Skewness......................... .718 1.21 -1.36 -1.01 1.73 -.756 1.1 .837 1.65 .760

WV PC-7

n ...................................... 12 18 6 15 6 12 6 11 3 6

Mean (ppm) .................... 60 70 11.7 14 75 70 7 7 1.27 .61

Standard Dev (ppm)........ 11 13 .82 4.9 6.7 26 1.3 6.0 .049 .21

Rel Std Dev (%).............. 17.5 18.2 7.00 34.0 8.91 37.7 18.3 82.1 3.83 35.6

Geometric Mean (ppm)... 61 70 11.6 14 75 70 7 7 1.27 .58

Dev of Means (%)........... 1.41 1.74 .20 5.52 .34 8.60 1.43 11.46 .05 5.74

Kurtosis........................... -.805 -1.14 -.300 -1.33 -2.08 -.563 -2.05 -.303 ERR -3.2

Skewness......................... .354 .042 .857 .454 -.488 -.527 .054 .611 -.586 .003

ND PC-8

n ...................................... 12 18 5 8 6 12 3 6 3 6

Mean (ppm) .................... 560 600 2.1 2.2 9 12 .79 .7 .41 .6

Standard Dev (ppm)........ 65 100 .22 .26 3.4 4.8 .050 .12 .024 .22

Rel Std Dev (%).............. 11.6 16.7 10.4 11.7 38.3 39.1 6.34 18.2 5.83 35.5

Geometric Mean (ppm)... 560 600 2.1 2.2 8 11 .79 .7 .41 .6

Dev of Means (%)........... .61 1.30 .45 .62 7.14 8.59 .14 1.44 .11 5.73

Kurtosis........................... -2.04 -.458 -2.37 -.130 -2.21 -.527 ERR -1.40 ERR -3.21

Skewness......................... .239 .641 -.559 -.380 -.115 .0785 -.59 -.199 -.609 .00375
APPENDIX 2 103

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Ag HP Ag All Cd HP Cd All Sn HP Sn All Sb HP Sb All Cs HP

UF PC-1

n...................................... 3 66636666

Mean (ppm) .................... .5 .3 .12 .12 .95 1.3 .51 .51 1.7

Standard Dev (ppm) ....... .14 .17 .057 .057 0 .39 .034 .034 .20

Rel Std Dev (%) ............. 29.8 50.2 49.7 49.7 0 30.5 6.64 6.64 12.0

Geometric Mean (ppm) .. .5 .3 .11 .11 .95 1.3 .51 .51 1.7

Dev of Means (%) .......... 2.79 10.22 9.95 9.95 0 4.09 .19 .19 .61

Kurtosis .......................... ERR .687 .664 .664 ERR -3.10 .364 .364 -3.16

Skewness ........................ 1.57 1.11 1.11 1.11 ERR .071 -.156 -.156 -.063

WY PC-2

n...................................... 3 66636666

Mean (ppm) .................... .24 .2 .11 .11 .323 .6 .18 .18 .195

Standard Dev (ppm) ....... .085 .11 .020 .020 0 .36 .021 .021 .010

Rel Std Dev (%) ............. 36.2 70.6 18.5 18.5 0 58.9 11.6 11.6 4.86

Geometric Mean (ppm) .. .23 .1 .11 .11 .323 .5 .18 .18 .195

Dev of Means (%) .......... 4.20 23.26 1.27 1.27 0 13.95 .58 .00579 .10

Kurtosis .......................... ERR .353 3.70 3.70 ERR .201 -1.62 -1.62 -1.22

Skewness ........................ 1.43 1.03 1.91 1.91 ERR 1.17 -.397 -.397 .198

IL PC-3

n...................................... 3 66636666

Mean (ppm) .................... .6 .5 .7 .7 .71 2 .84 .84 1.1

Standard Dev (ppm) ....... .18 .18 .14 .14 .094 1.1 .062 .062 .29

Rel Std Dev (%) ............. 28.9 36.5 19.4 19.4 13.3 67.7 7.45 7.45 25.3

Geometric Mean (ppm) .. .6 .5 .7 .7 .70 1 .83 .83 1.1

Dev of Means (%) .......... 2.96 5.19 1.45 1.45 .06 22.21 .24 .24 2.82

Kurtosis .......................... ERR .333 1.66 1.66 ERR -.966 1.49 1.49 -3.17

Skewness ........................ 1.39 ́10-15 1.14 1.36 1.36 1.73 .809 -.882 -.882 .019

PITT PC-4

n...................................... 3 66636666

Mean (ppm) .................... .3 .2 .08 .08 .552 .9 .22 .22 .75

Standard Dev (ppm) ....... .13 .14 .028 .028 .0053 .46 .022 .022 .061

Rel Std Dev (%) ............. 42.1 73.3 34.3 34.3 .93 50.6 10.0 10.0 8.16

Geometric Mean (ppm) .. .3 .2 .08 .08 .573 .8 .22 .22 .75

Dev of Means (%) .......... 6.43 23.82 4.83 4.83 0 10.7 .43 .43 .28

Kurtosis .......................... ERR .213 -.779 -.779 ERR .120 -.890 -.890 -2.24

Skewness ........................ .423 1.14 .738 .738 1.73 .954 -.340 -.340 -.432

POC PC-5

n...................................... 3 65636666

Mean (ppm) .................... .23 .16 .08 .07 .371 40 .4 .4 .24

Standard Dev (ppm) ....... .093 .090 .014 .02 0 57 .14 .14 .024

Rel Std Dev (%) ............. 40.6 55.6 19.0 30.9 0 159 33.8 33.8 9.91

Geometric Mean (ppm) .. .22 .15 .074 .07 .371 5 .4 .4 .24

Dev of Means (%) .......... 6.04 12.2 1.61 5.12 0 700 4.81 4.81 .40

Kurtosis .......................... ERR .760 1.119 -.088 ERR 4.29 -1.69 -1.69 .192

Skewness ........................ .242 1.33 -.968 -.920 ERR 2.02 .508 .508 .876

UT PC-6

n...................................... 3 65536666

Mean (ppm) .................... .15 .3 .07 .07 .17 .3 .10 .10 .14

Standard Dev (ppm) ....... .050 .18 .012 .012 .03 .12 .012 .012 .012

Rel Std Dev (%) ............. 32.8 58.7 17.5 17.5 15.8 45.8 12.3 12.3 8.68

Geometric Mean (ppm) .. .15 .3 .07 .07 .17 .2 .10 .10 .14

Dev of Means (%) .......... 4.21 19.1 1.19 1.19 .89 9.21 .60 .60 .32

Kurtosis .......................... ERR -2.11 -1.52 -1.52 ERR -1.99 .00139 .00139 -1.55

Skewness ........................ -1.18 .155 .824 .824 -1.73 .471 .967 .967 -.706

WV PC-7

n...................................... 3 66636666

Mean (ppm) .................... 1.2 .8 .07 .07 1.75 1.8 .54 .54 2.1

Standard Dev (ppm) ....... .53 .55 .016 .016 0 .18 .041 .041 .27

Rel Std Dev (%) ............. 43.2 64.6 24.9 24.9 0 10.1 7.65 7.65 12.9

Geometric Mean (ppm) .. 1.2 .7 .07 .07 1.75 1.8 .54 .54 2.1

Dev of Means (%) .......... 7.17 16.9 3.23 3.23 0 .41 .23 .23 .63

Kurtosis .......................... ERR .243 .971 -.971 ERR .666 3.66 3.66 -3.30

Skewness ........................ -.031 1.21 -1.23 -1.23 ERR .961 1.75 1.75 -.011

ND PC-8

n...................................... 3 36634566

Mean (ppm) .................... .15 .15 .043 .043 .4 .6 .15 .15 .09

Standard Dev (ppm) ....... .062 .062 .0072 .0072 .16 .45 .010 .020 .012

Rel Std Dev (%) ............. -39.7 39.7 18 18 43.3 76.2 6.80 12.7 13.0

Geometric Mean (ppm) .. .15 .15 .041 .041 .4 .5 .15 .15 .09

Dev of Means (%) .......... 5.76 5.76 1.58 1.58 5.84 21.9 .19 .64 .77

Kurtosis .......................... ERR ERR 1.52 1.52 ERR 1.96 -.906 2.45 1.86

Skewness ........................ .219 .219 -1.45 -1.45 1.73 1.53 -.516 1.33 -1.34
104 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Ba HP Ba All La HP La All Ce HP Ce All Pr HP Pr All Nd HP Nd All

UF PC-1

n...................................... 12 21 9 15 9 133346

Mean (ppm).................... 56 60 9 10 17 20 1.9 1.9 7.7 8

Standard Dev (ppm) ....... 5.7 13 1.2 6.0 1.5 12 .16 .16 .68 1.6

Rel Std Dev (%) ............. 10.2 21.1 15.4 60.5 8.6 52.4 8.08 8.08 8.87 21.3

Geometric Mean (ppm) .. 56 60 9 9 17 20 1.9 1.9 7.7 7

Dev of Means (%) .......... .46 2.18 1.08 9.62 .35 10.3 .23 .23 .31 2.05

Kurtosis .......................... .162 .742 -1.64 13.1 .121 2.09 ERR ERR 3.90 .983

Skewness ........................ 1.09 .855 -.105 3.52 -1.23 1.75 -1.73 -1.73 -1.97 -.402

WY PC-2

n...................................... 9 21 6 12 8 143333

Mean (ppm).................... 300 300 4.7 5 8 12 .93 .93 3.4 3.4

Standard Dev (ppm) ....... 22 120 .82 2.0 1.9 8.1 .085 .085 0 0

Rel Std Dev (%) ............. 7.17 40.0 17.6 37.3 23.7 69.9 9.08 9.08 0 0

Geometric Mean (ppm) .. 290 200 4.6 5 8 10 .93 .93 3.4 3.4

Dev of Means (%) .......... .24 35.37 1.39 5.29 3.10 17.20 .28 .28 0 0

Kurtosis .......................... -.976 1.25 -1.18 4.76 .677 5.17 ERR ERR ERR ERR

Skewness ........................ .168 -1.30 -.623 2.00 -1.08 2.21 -.176 -.176 ERR ERR

IL PC-3

n...................................... 12 21 5 12 9 133334

Mean (ppm).................... 83 90 6.0 9 11 20 1.4 1.4 4.9 5.6

Standard Dev (ppm) ....... 8.9 23 .22 4.1 2.7 16 .17 .17 0 .81

Rel Std Dev (%) ............. 10.8 26.1 3.50 45.1 25.6 81.6 14.1 14.1 0 14.5

Geometric Mean (ppm) .. 82 90 6.0 8 10 20 1.3 1.3 4.9 5.5

Dev of Means (%) .......... .54 3.31 .05 8.97 3.46 27.17 .71 .71 0 .82

Kurtosis .......................... -1.16 -.0928 -3.33 -.829 -1.32 4.30 ERR ERR ERR 4.00

Skewness ........................ -.078 2 .519 -.604 .881 -.822 2.05 -1.73 -1.73 ERR 2.00

PITT PC-4

n...................................... 12 21 8 14 9 123336

Mean (ppm).................... 40 40 5.1 6 10 12 1.12 1.12 4.3 4.1

Standard Dev (ppm) ....... 4.5 12 .86 5.1 1.3 5.2 .058 .058 .52 .50

Rel Std Dev (%) ............. 11.2 29.0 16.7 84.8 12.5 43.9 5.09 5.09 12 13.5

Geometric Mean (ppm) .. 40 40 5.1 5 10 11 1.12 1.12 4.3 4.1

Dev of Means (%) .......... .55 3.49 1.18 24.5 .77 7.32 .08 .08 .51 .81

Kurtosis .......................... 1.78 1.80 -2.12 11.0 2.36 3.48 ERR ERR ERR -.127

Skewness ........................ 1.05 .888 .541 3.12 -1.32 1.84 1.73 1.73 1.73 -.956

POC PC-5

n...................................... 9 21 6 15 8 153336

Mean (ppm).................... 200 200 6.2 5 11 11 1.31 1.31 5.0 5.5

Standard Dev (ppm) ....... 14 130 .63 2.6 1.6 3.5 .090 .090 .29 .77

Rel Std Dev (%) ............. 7.17 65.0 10.1 47.5 14.8 33.4 6.19 6.19 5.81 13.9

Geometric Mean (ppm) .. 190 100 6.2 5 11 10 1.31 1.31 5.0 5.5

Dev of Means (%) .......... .24 35.8 .43 17.3 1.10 6.19 .13 .13 .11 .81

Kurtosis .......................... .752 1.25 -2.17 -.548 .967 1.74 ERR ERR ERR 1.86

Skewness ........................ -.139 .894 -.345 -.287 -1.45 .331 -.722 -.722 1.73 1.36

UT PC-6

n...................................... 8 14 6 12 6 123656

Mean (ppm).................... 35 34 2.9 5 4.7 8 .55 .48 2.1 2.2

Standard Dev (ppm) ....... 2.0 3.7 .50 3.1 .14 4.8 .023 .069 .32 .44

Rel Std Dev (%) ............. 5.62 10.8 17.3 67.7 3.02 61.2 4.30 14.5 18.3 21.1

Geometric Mean (ppm) .. 35 34 2.9 4 4.7 7 .55 .48 2.1 2.2

Dev of Means (%) .......... .14 .55 1.31 18.1 .04 13.9 .06 .90 1.41 1.96

Kurtosis .......................... -1.16 -.164 -2.95 .200 -.065 2.89 ERR -2.35 -2.05 -.620

Skewness ........................ -.752 -.0660 .390 1.38 -.846 1.79 -1.73 -.0511 -.543 -.056

WV PC-7

n...................................... 12 18 9 15 9 153569

Mean (ppm).................... 120 140 19 17 34 40 4.1 3 14 15

Standard Dev (ppm) ....... 17 37 2.4 3.0 3.5 11 .21 1.2 1.6 3.1

Rel Std Dev (%) ............. 14.1 26.1 12.6 17.8 10.2 30.0 4.78 38.1 12.0 20.4

Geometric Mean (ppm) .. 120 130 19 17 34 40 4.1 3 13 15

Dev of Means (%) .......... .78 2.82 .72 1.51 .48 3.74 .09 7.08 .56 1.86

Kurtosis .......................... 3.37 1.28 -.914 -.928 -.614 1.59 ERR -3.17 -1.535 -1.67

Skewness ........................ 1.85 1.52 .018 .121 -.678 1.34 -.077 -.546 .358 .355

ND PC-8

n...................................... 12 18 6 12693355

Mean (ppm).................... 500 600 2.5 4 4.3 9 .43 .43 1.8 1.8

Standard Dev (ppm) ....... 100 210 .51 2.5 .38 7.4 .058 .058 .57 .57

Rel Std Dev (%) ............. 20.0 35.0 21.4 63.2 9.16 82.7 14.0 14.0 30.5 30.5

Geometric Mean (ppm) .. 500 600 2.4 4 4.3 7 .43 .43 1.8 1.8

Dev of Means (%) .......... 1.66 4.93 1.97 16.3 .34 32.8 .62 .62 4.9 4.9

Kurtosis .......................... -.729 .434 -3.31 1.37 -1.70 -1.41 ERR ERR 2.4 2.4

Skewness ........................ .713 1.25 .005 1.47 .482 .924 1.73 1.73 -1.2 -1.2
APPENDIX 2 105

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

Sm HP Sm All Eu HP Eu All Tb HP Yb HP Yb All Hf HP Ta HP

UF PC-1

n ...................................... 6 6 6 6 66966

Mean (ppm) .................... 1.8 1.8 .37 .37 .248 .85 .85 .8 .21

Standard Dev (ppm)........ .24 .24 .035 .035 .0190 .073 .059 .11 .020

Rel Std Dev (%).............. 14.3 14.3 9.63 9.63 7.66 8.6 6.97 14.5 9.30

Geometric Mean (ppm) .. 1.7 1.7 .37 .37 .247 .85 .84 .7 .21

Dev of Means (%)........... .87 .87 .39 .39 .25 .32 .22 .86 .37

Kurtosis........................... -2.89 -2.89 -2.17 -2.17 .088 -1.63 -.52 -1.12 -1.56

Skewness......................... -.132 -.132 -.217 -.217 -.026 -.61 -.45 .617 -.24

WY PC-2

n ...................................... 6 6 6 666966

Mean (ppm) .................... .8 .8 .18 .18 .11 .40 .36 .64 .12

Standard Dev (ppm)........ .15 .15 .021 .021 .009 .048 .071 .053 .019

Rel Std Dev (%).............. 18.0 18.0 12.0 12.0 8.96 12.2 19.6 8.17 14.8

Geometric Mean (ppm) .. .8 .8 .18 .18 .11 .39 .36 .64 .13

Dev of Means (%)........... 1.39 1.39 .64 .64 .34 .66 1.92 .28 .98

Kurtosis........................... -2.97 -2.97 -1.37 -1.37 -2.08 -.54 -.23 .108 .270

Skewness......................... -.133 -.133 -.934 -.934 -.206 -.848 -.633 -.288 -.694

IL PC-3

n ...................................... 6 6 6 6 66966

Mean (ppm) .................... 1.1 1.1 .21 .21 .14 .52 .56 .7 .18

Standard Dev (ppm)........ .15 .15 .021 .021 .011 .015 .061 .15 .013

Rel Std Dev (%).............. 13.6 13.6 10.4 10.4 8.0 2.85 10.9 22.4 7.04

Geometric Mean (ppm) .. 1.1 1.1 .21 .21 .14 .52 .55 .6 .18

Dev of Means (%)........... .91 .91 .47 .47 .27 .03 .50 1.95 .23

Kurtosis........................... 4.90 4.90 -1.37 -1.37 -.173 4.15 .670 1.38 2.79

Skewness......................... -2.16 -2.16 -.991 -.991 -.586 1.91 1.31 1.26 -1.56

PITT PC-4

n ...................................... 6 6 6 666966

Mean (ppm) .................... 1.0 1.0 .19 .19 .12 .450 .48 .56 .15

Standard Dev (ppm)........ .15 .15 .025 .025 .011 .0243 .063 .062 .019

Rel Std Dev (%).............. 16.0 16.0 12.0 12.0 8.87 5.14 13.08 11.2 12.4

Geometric Mean (ppm) .. .9 .9 .19 .19 .12 .449 .48 .56 .15

Dev of Means (%)........... 1.13 1.13 .60 .60 .33 .11 .70 .52 .65

Kurtosis........................... -1.83 -1.83 -2.74 -2.74 -2.48 2.04 4.57 -2.64 -2.86

Skewness......................... -.518 -.518 .033 .033 -.371 -.11 1.95 .018 -.108

POC PC-5

n ...................................... 6 9 6 666966

Mean (ppm) .................... 1.1 1.0 .22 .22 .165 .56 .53 .50 .12

Standard Dev (ppm)........ .13 .20 .015 .015 .0074 .012 .059 .073 .011

Rel Std Dev (%).............. 12.0 20.6 6.61 6.61 5.39 2.11 11.24 14.5 9.48

Geometric Mean (ppm) .. 1.1 1.0 .22 .22 .164 .56 .52 .50 .11

Dev of Means (%)........... .62 2.01 .18 .18 .12 .02 .60 .87 .40

Kurtosis........................... -2.59 -1.45 -1.84 -1.84 -1.09 -.22 -.805 -2.73 -.802

Skewness......................... -.309 -.147 .660 .660 -.52 -.635 -.964 .217 .15

UT PC-6

n ...................................... 6 9 6 766966

Mean (ppm) .................... .44 .42 .092 .094 .056 .20 .20 .52 .052

Standard Dev (ppm)........ .076 .069 .0086 .0105 .0051 .008 .009 .053 .0087

Rel Std Dev (%).............. 17.3 16.7 9.54 11.31 9.01 3.91 4.35 10.3 16.7

Geometric Mean (ppm) .. .43 .41 .091 .094 .056 .20 .20 .52 .052

Dev of Means (%)........... 1.26 1.17 .38 .56 .33 .06 .08 .43 1.28

Kurtosis........................... -3.27 -1.65 -1.15 -.37 .395 -.509 -.008 -.57 .02

Skewness......................... .0210 .852 -.585 -.07 1.04 -.429 .067 .72 -1.08

WV PC-7

n ...................................... 6 8 6 966966

Mean (ppm) .................... 3.2 2.8 .64 .6 .398 1.6 1.6 2.1 .63

Standard Dev (ppm)........ .40 .76 .036 .12 .020 .12 .15 .28 .043

Rel Std Dev (%).............. 13.1 27.1 5.75 19.6 5.08 7.49 9.59 12.6 6.99

Geometric Mean (ppm) .. 3.1 2.7 .64 .6 .397 1.6 1.6 2.1 .63

Dev of Means (%)........... .70 3.82 .14 1.67 .11 .24 .403 .68 .20

Kurtosis........................... -3.03 -1.03 -1.31 1.74 .689 -1.27 -1.32 -3.22 .190

Skewness......................... -.098 -.644 .416 .76 .318 -.256 .362 -.049 -.49

ND PC-8

n ...................................... 6 7 6 666963

Mean (ppm) .................... .33 .35 .07 .07 .055 .26 .24 .38 .093

Standard Dev (ppm)........ .10 .10 .015 .015 .0044 .041 .043 .046 .0040

Rel Std Dev (%).............. 28.4 28.4 22.4 22.4 8.06 15.9 18.0 12.4 4.36

Geometric Mean (ppm) .. .34 .34 .07 .07 .055 .26 .24 .38 .093

Dev of Means (%)........... 4.11 4.11 2.10 2.10 .26 1.02 1.36 .63 .06

Kurtosis........................... -.869 -.869 -2.52 -2.52 1.05 -1.18 -.237 -1.95 ERR

Skewness......................... -.559 -.559 .138 .138 1.43 .548 .854 .41 -1.73
106 THE CHEMICAL ANALYSIS OF ARGONNE PREMIUM COAL SAMPLES

Appendix 2. Statistical parameters for the data in appendix 1—Continued. 

W HP W All Pb HP Pb All Bi HP Bi All Th HP Th All U HP

UF PC-1

n...................................... 6 6 6 12 3 3 6 66

Mean (ppm).................... 1.2 1.2 7.5 8 .117 .117 2.5 2.5 1.0

Standard Dev (ppm) ....... .13 .13 .33 1.5 .0058 .0058 .48 .48 .18

Rel Std Dev (%) ............. 11.0 11.0 4.39 18.4 4.95 4.95 19.2 19.2 18.4

Geometric Mean (ppm) .. 1.1 1.1 7.5 8 .117 .117 2.5 2.5 1.0

Dev of Means (%) .......... .48 .48 .08 1.54 .08 .08 1.96 1.96 1.55

Kurtosis .......................... -1.56 -1.56 1.34 -.902 ERR ERR 4.82 4.82 -2.91

Skewness ........................ .56 .56 -1.22 .469 -1.73 -1.73 -2.12 -2.12 .102

WY PC-2

n...................................... 6 6 6 9 3 3 6 66

Mean (ppm).................... .42 .42 2.3 2.6 .053 .053 1.6 1.6 .58

Standard Dev (ppm) ....... .055 .055 .75 .90 .0034 .0034 .25 .25 .054

Rel Std Dev (%) ............. 12.7 12.7 33.2 34.3 6.45 6.45 16.2 16.2 9.35

Geometric Mean (ppm) .. .42 .42 2.2 2.5 .053 .053 1.6 1.6 .58

Dev of Means (%) .......... .66 .66 4.72 5.84 .14 .14 .95 .95 .35

Kurtosis .......................... -1.68 -1.68 -3.01 -1.03 ERR ERR 2.21 2.21 -2.66

Skewness ........................ .535 .535 .122 .096 -1.73 -1.73 1.17 1.17 -4.6 ́10-15

IL PC-3

n...................................... 6 6 6 12 2 2 6 66

Mean (ppm).................... 1.73 1.73 7 9 .088 .088 2.1 2.1 5

Standard Dev (ppm) ....... .256 .256 1.1 3.0 .0011 .0011 .19 .19 1.2

Rel Std Dev (%) ............. 14.4 14.4 15.6 32.6 1.61 1.61 9.28 9.28 23.1

Geometric Mean (ppm) .. 1.69 1.69 7 9 .088 .088 2.1 2.1 5

Dev of Means (%) .......... .82 .82 1.04 4.59 .01 .01 .33 .33 2.27

Kurtosis .......................... -.637 -.637 -2.91 -.637 ERR ERR 3.31 3.31 -2.70

Skewness ........................ .929 .929 -.019 .885 ERR ERR 1.81 1.81 .164

PITT PC-4

n...................................... 6 6 6 12 3 5 6 66

Mean (ppm).................... .82 .82 3.4 5 .117 .8 1.5 1.5 .5

Standard Dev (ppm) ....... .049 .049 .50 1.8 .0053 .91 .15 .15 .10

Rel Std Dev (%) ............. 5.82 5.82 15.0 40.1 4.95 118 9.52 9.52 21.4

Geometric Mean (ppm) .. .82 .82 3.3 4 .116 .3 1.5 1.5 .5

Dev of Means (%) .......... .15 .15 .94 6.86 .08 125 .36 .36 2.02

Kurtosis .......................... -.80 -.80 -3.14 -.680 ERR -2.36 1.66 1.66 -2.37

Skewness ........................ .43 .43 .066 .962 -1.73 .776 1.34 1.34 -.228

POC PC-5

n...................................... 6 6 6 12 3 3 6 66

Mean (ppm).................... 1.0 1.0 2.1 5 .051 .051 1.16 1.16 .57

Standard Dev (ppm) ....... .16 .16 .40 3.9 .0022 .0022 .043 .043 .071

Rel Std Dev (%) ............. 16.7 16.7 19.3 78.5 4.06 4.06 3.71 3.71 12.5

Geometric Mean (ppm) .. .96 .96 2.0 4 .051 .051 1.15 1.15 .57

Dev of Means (%) .......... 1.17 1.17 1.68 29.52 .06 .06 .06 .06 .68

Kurtosis .......................... -1.17 -1.17 -2.96 -.0035 ERR ERR -1.48 -1.48 -1.81

Skewness ........................ .281 .281 -.064 1.17 -1.29 -1.29 -.809 -.809 -.400

UT PC-6

n...................................... 6 6 5 8 3 3 6 66

Mean (ppm).................... .45 .45 1.52 1.7 .035 .035 .60 .60 .79

Standard Dev (ppm) ....... .062 .062 .084 .25 .0007 .0007 .025 .025 .056

Rel Std Dev (%) ............. 13.53 13.53 5.50 15.0 1.63 1.63 4.13 4.13 7.08

Geometric Mean (ppm) .. .450 .450 1.52 1.7 .035 .035 .60 .60 .78

Dev of Means (%) .......... .78 .78 .12 .94 .01 .01 .07 .07 .21

Kurtosis .......................... -2.85 -2.85 -.612 -.333 ERR ERR 3.37 3.37 -.674

Skewness ........................ -.182 -.182 -.512 .968 1.73 1.73 -1.70 -1.70 -.502

WV PC-7

n...................................... 5 6 6 9 3 3 6 66

Mean (ppm).................... 1.7 4 12.1 13 .23 .23 6.4 6.4 1.9

Standard Dev (ppm) ....... .52 6.5 0 2.2 0 0 .15 .15 .29

Rel Std Dev (%) ............. 31.3 151.0 0 16.4 0 0 2.33 2.33 15.3

Geometric Mean (ppm) .. 1.62 2 12.1 13 .23 .23 6.4 6.4 1.9

Dev of Means (%) .......... 3.56 80.2 0 1.06 0 0 .02 .02 .98

Kurtosis .......................... 2.29 5.89 ERR 1.94 ERR ERR -1.33 -1.33 -3.09

Skewness ........................ 1.42 2.42 ERR 1.72 ERR ERR -.315 -.315 .0423

ND PC-8

n...................................... 6 6 6 9 0 0 3 65

Mean (ppm).................... .36 .36 1.5 1.8 ERR ERR 1.1 .88 .46

Standard Dev (ppm) ....... .060 .060 .34 .67 ERR ERR .04 .21 .04

Rel Std Dev (%) ............. 16.8 16.8 23.0 35.8 ERR ERR 3.79 .18 7.87

Geometric Mean (ppm) .. .35 .35 1.4 1.7 ERR ERR 1.1 .23 .46

Dev of Means (%) .......... 1.34 1.34 2.72 6.08 ERR ERR .05 .86 .24

Kurtosis .......................... 2.21 2.21 3.07 .034 ERR ERR ERR -2.20 1.9

Skewness ........................ -1.10 -1.10 -1.20 .564 ERR ERR .72 -.228 .544
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State. A series of international MIS’s is also available.

Published on an annual basis, Mineral Commodity Summaries is the earliest Government publication to furnish estimates

covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs,

tariffs, and 5-year salient statistics for more than 90 individual

minerals and materials.

The Minerals Yearbook discusses the performance of the

worldwide minerals and materials industry during a calendar year,

and it provides background information to assist in interpreting

that performance. The Minerals Yearbook consists of three volumes. Volume I, Metals and Minerals, contains chapters about

virtually all metallic and industrial mineral commodities important

to the U.S. economy. Volume II, Area Reports: Domestic, contains

a chapter on the minerals industry of each of the 50 States and

Puerto Rico and the Administered Islands. Volume III, Area Reports: International, is published as four separate reports. These

reports collectively contain the latest available mineral data on

more than 190 foreign countries and discuss the importance of

minerals to the economies of these nations and the United States.

PERMANENT CATALOGS

‘Publications of the U.S. Geological Survey, 1879-1961”

and ‘Publications of the U.S. Geological Survey, 1962-1970” are

available in paperback book form and as a set of microfiche.

‘Publications of the U.S. Geological Survey, 1971-1981” is

available in paperback book form (two volumes, publications

listing and index) and as a set of microfiche.

Annual supplements for 1982, 1983, 1984, 1985, 1986, and

subsequent years are available in paperback book form.